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IIT Foundation Class 8 Science Chapter 5 to 10

Question Bank - 9

103 Qs

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Choose only words from the following list and write down the appropriate word to fill in the blanks below-
anode,cathode,electrode,electrolyte,nickel    
(a) ..........
 which must be a solution containing ions.                                                       

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To electroplate an article with nickel requires the article to be placed at ........

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The part of the cell in which the electroplating is carried out is ..............

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Choosing only words from the following list write down the appropriate words to fill in the blanks below (anions, anode, cathode, cationa, electrode, electrolyte, nickel, voltameter)

To electroplate an article with nickel requires an:
The ________ of the cell is made from pure nickel.

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The ions which are attracted to the negative electrode and discharge are call

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What is an electrolyte ? 

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Classify the following substances under three headings.
Strong electrolytes ,Weak electrolytes 

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Most liquids that conduct electricity are solutions of______,_______ and _______. Fill in the blanks. 

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The passage of an electric current through a solution causes   ................ effects.

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If you pass current through copper sulphate solution, copper gets deposited on the plate connected to ______terminal of the battery. FIll in the blank.

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Fill the appropriate word in the blank
The process of depositing a layer of any desired metal on another material by means of  electricity is called ________.

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LED glows even when a ______ electric current passes through it. Fill in the blank.

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Pure water consists entirely of _____________ (ions / molecules). 

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We can expect that pure water normally _________ electricity. Fill in the blank. 

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To carry out the so-called electrolysis of water, sulphuric acid is added to water. How does the addition of sulphuric acid produce a conducting solution ?

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Copy and complete the following sentences ?

With platinum electrodes hydrogen is liberated at the ........... and oxygen at the .......... during the electrolysis of acidified water.

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During the electrolysis of acidified water, what is the ratio of the volumes of hydrogen produced to the volume of oxygen ?

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Give the equation for the discharge of ion at the cathode during the electrolysis of acidified water ?

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Name a liquid which is a non-electrolyte.

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Name a solid which undergoes electrolysis when molten.

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Copy and complete the following table which refers to two practical applications of electrolysis.
AnodeElectrolyteCathode
Silver plating a spoonSolution of potassium argentocyanide
Purification of copper

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What ions must be present in a solution used for electroplating a particular metal?

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Acidified water is electrolysed by using carbon electrodes. What is produced at positive carbon electrode?

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Acidified water is electrolysed by using carbon electrodes. What is produced at negative carbon electrode?

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In case of a fire, before the firemen use the water hoses, they shut off the main electrical supply for the area. Explain why they do this.

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Seema had heard that rainwater is as good as distilled water. So she collected some rainwater in a clean glass tumbler and tested it using a tester. To her surprise, she found that the compass needle showed deflection. What could be the reasons?

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Fill in the blanks :
Electrolysis is the passage of_______ (electricity / electrons) through a liquid or a solution accompanied by a _______ (physical/ chemical) change.

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Fill in the blanks :
A ______  (generator / cell) is used to operate small devices such as calculator and TV remote.

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A __________ is a combination of two or more cells connected end to end.

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Fill in the blanks :
________  (Dry cell/ Wet cell) is a primary cell which cannot be charged.

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Complete the sentence by using the correct words given in the brackets:
A ________ (generator / transformer/motor/transducer) is a source of electricity that generates large amount of electricity in a power house.

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A solar cell converts ________ (sound / light) energy to_______ (light /  electrical) energy. Fill the blanks. 

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A generator converts _____ (electrical / mechanical) energy to ____(electrical / mechanical) energy.

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.......... (chemical / physical) reaction takes place.

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Water is broken down into its constituent elements .......... and .......... .

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The chemical reaction is

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Hydrogen gas is liberated at the .......... (negative / positive) electrode called ..........

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Oxygen gas is liberated at the .......... (negative / positive) electrode called the .......... .

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Solutions which are decomposed due to the current passed through them are called .......... .

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Fill in the blanks from the options given below to make the statement complete.

When an electric current is passed through water containing a small amount of dilute sulphuric acid, then using .......... as the method, we can coat one metal with another using an electric current.

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Match the following:

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The electrode in voltameter is connected to +ve terminal of a battery is 

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The electrode in a voltmeter connected to -ve terminal of a battery is

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Name the substance dissolved in pure water to make it a conductor of electricity.

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 The process of electrical coating of a superior metal on base metal is known as_______________.

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Positive terminal of a voltaic cell is called as :

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Negative terminal of a voltaic cell is 

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The whole apparatus used for electrolysis is termed as :

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Cell which cannot be charged is 

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A liquid, or solution, which conducts electricity with accompanying chemical change is known as :

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A compound, which is soluble in water and the only negative ions in the solution are hydroxide ions.

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Explain why copper, though a good conductor of electricity, is a non-electrolyte.

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Name the gas released at the cathode when acidulated water is electrolysed.

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Explain why solid sodium chloride does not allow electricity to pass through

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Electrons are getting added to an element Y. Which electrode will Y migrate to during electrolysis?

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A solution of silver nitrate is a good electrolyte but it is not used for electroplating an article with silver. Why?

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Describe how direct current differs form alternating current.

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Write the equation of the reactions which take place at the cathode and anode when acidified water is electrolysed.

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An electrode A is connected to the positive terminal of battery and electrode B to the negative terminal. Give the names of the electrodes A and B.

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An electrode A is connected to the positive terminal of battery and electrode B to the negative terminal. Which electrode is the oxidising electrode?

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Which device converts chemical energy into electrical energy ?

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An object becomes charged when the atoms in the object gain or lose.

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For a cell to produce a current, the electrodes of the cell must

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The outlets in your home provide.

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Ammonium chloride in dry cell is

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You can make a cell by using an apple, a strip of copper, and a stripe of silver, Explain how you would construct the cell. What type of cell did you make? Explain your answer.

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Name three liquids, which when tested in the manner shown in the figure, may cause the magnetic needle to deflect.

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The bulb does not glow in the set up shown in the figure. List the possible reasons. Explain your answer.

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Metals are good conductors because

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A tester is used to check the conduction of electricity through two liquids. Labeled A and B. it is found the bulb of the tester glows brightly for liquids A while it glows very dimly for liquid B. what conclusion would you draw?

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Surbhi sets up the apparatus as shown to test the electrical conductivity of vinegar. She finds that the current passing through the circuit is not strong enough to make the bulb grow. What other device could she use in place of the bulb so that it glows even under weak current

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What precausions need to be taken by Surbhi while using the new device ?

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State whether true or false : 
There is no electrolyte in a dry cell.

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State whether true or false : 
If a liquid conducts electricity. It is called electrolyte.

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State whether true or false : 
A bulb is used in place of LED to detect weak currents.

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State whether true or false : 

The current obtained by the primary and the secondary cells is direct current.

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State whether true or false :
If current is passed through copper sulphate solutions, copper gets deposited on the plate connected to the negative terminal of the battery.

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State whether true or false :
A piece of fresh potato does not conduct electricity at all.

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State whether true or false :
Rain water is a non-conductor of electricity.

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Iron and steel protected form corrosion by coating them with a layer of tin or chromium metals. This process is called

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When an impure copper rod acts the anode and the pure copper rod acts as the cathode in an electrolysis experiment, then which of the following occurs?

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On electrolysis, water splits into :

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During the process of electrolysis of water, dilute sulphuric acid splits into

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If an electric current is passed through a cut potato for some time, then there would be a colored spot on the potato around one wire and no such spot around the other wire.
State the colour of the spot.

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Around which electrode, (positive or negative electrode) the coloured spot is formed.

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The above happens due to which effect of an electric current?

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Which of the following two processes utilize the phenomenon of chemical effect of electric current?

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In an electrolytic cell, the electrode that is connected to the positive terminal of a battery is

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Will the bulb glow if B is dipped in pure water?

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An electrolyte is

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In electrolysis

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Iron vessels are coated with tin to

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Coating of iron with zinc is known as

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When current is passed through molten sodium chloride.

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A particular solutions contains molecules and ions of the solute so it is a 

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A compound which liberates reddish brown gas around the anode during electrolysis in its molten state is -

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Which of the following is a strong electrolyte?

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Mr. Ramu wants to electroplate his key chain with nickel to prevent rusting. The cathode used for this electroplating is

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Name the anode, the cathode, and the electrolyte used in electrorefining of impure copper

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Sameer wants to electroplate his key chain with nickel to prevent rusting. For this electroplating give the reaction at the cathode.

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Give one example of electroplating of a metal along with the reactions at cathode and anode.

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Three different electrolytic cells A, B, and C are connected in separate circuits. Electrolytic cell A contains sodium chloride solution. When the circuit is completed a bulb in the circuit glows brightly. Electrolytic cell B contains acetic acid solution and in this case the bulb in the circuit glows dimly. The electrolytic cell C contains sugar solution and the bulb does not glow. Give a reason for each of these observations.

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A process in which a thin film of a metal like gold, silver, etc., is deposited on another metallic article with the help of electricity.

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Self Assessment - 9

39 Qs

Related questions

A child starting in a coastal region tests the drinking water and also the sea with his tester. He finds that the compass needle deflects more in the case of sea water. Can you explain the reason ?

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Is it safe for an electrician to carry out electrical repairs outdoors during heavy downpour ? Explain

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________electrode is made of zinc. 

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Positive electrode is made up of:

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The liquid in the simple cell id dilute______acid. Fill in the blank. 

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Look at the diagram and answer the following.
A light bulb connected to the terminals of a simple cell glows and then dims very quickly. This is because bubbles of _____ are formed in the cell. Fill in the blank. 

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Are there bubbles formed

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What name is given to the formation of these bubbles ?

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The e.m.f. of a cell is _____ the voltage across its terminals when no current flows. Fill in the blank.

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What is the value of the e.m.f. of a simple cell ?

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What is the e.m.f. of a dry cell ?

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Which acid is used in a car battery ?

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What gases are liberated when a car battery is being recharged ?

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Does the strength of the sulphuric acid ________ during the discharge of a car battery? Fill in the blank. 

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What name is given to substances, such as dilute sulphuric acid, which can be decomposed by an electric current ?

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Fill appropriate word in the blank
The cathode of an electrolytic cell is connected to the _________ terminal of a d.c. supply.

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In metals, the current carriers are electrons, in electrolytes, the current carriers are ________. Fill in the blank with appropriate option. 

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Name three types of substances which produce a chemical effect when electric current is passed through them.

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What is the nature of chemical changes which takes place as a result of the chemical effect of an electric current ?

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Name given to the process of depositing a layer of any desired material, by means of electricity is known as .....

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Look at the diagram which shows electrolysis of water and answer the following questions.
What substances are the electrodes made of?

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Look at the diagram which shows electrolysis of water and answer the following questions.
What is produced at A is the ........ electrode called ........... It is connected to the .......... terminal of the battery.

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Look at the diagram which shows electrolysis of water and answer the following questions.
What is produced at B is the .......... electrode called .......... which is connected to the ........... terminal of the battery.

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Look at the diagram which shows electrolysis of water and answer the following questions.
What is produced at positive carbon electrode (anode) ?

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Look at the diagram which shows electrolysis of water and answer the following questions.
What is produced at negative carbon electrode (cathode) ?

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What name is given to the cell in which electrolysis takes place ?

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Which is the best instrument for testing the state of charge of car battery ?

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The diagram shows the process of purification of copper metal. A thick copper plate of impure copper and a thin copper plate are immersed in a metal sulphate solution and an electric current is passed through it. Which metal solution is taken as electrolyte ?

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Which electrode is connected to the positive terminal of the battery ?

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Which electrode is connected to the negative terminal of the battery ?

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What is liberated at the cathode ? Explain.

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Does the copper anode (increase/decrease/remains unchanged) in weight ?

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The chemical reaction due to passage of electric current depends on

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Tin cans, used for storing food are made by electroplating

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The electrolyte in dry cell is

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A cell in which chemical reactions are reversible is

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Consider the following statements about electroplating:
I. Electroplating is the coating of metal objects with a thin layer of a different metal.
II. Electroplating makes objects look more attractive and protects them from corrosion and rusting.
III. Electroplating forms and envelops around the object to protect them from magnetism.
Which of the above statements is true ?

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The diagram shows a tester consisting of a battery and LED whose open ends are dipped in a liquid. It is observed that even after some time, LED does not glow. Could it be due to the liquid being

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Which of the following types of a energy conversion takes place inside a battery ?

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Question Bank - 7

94 Qs

Related questions

A camera has a lens in it. The nature of the lens is

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Microscopes are used for magnification:

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Telescopes are used to obtain an .................. image of a ........... object.

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Fill in the blanks:
In our eyes an image of objects we wish to view is made at the _________ .

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State whether the following statement is True or False.
The instrument that is used to see things of celestial bodies like stars and planets is called as gyroscope

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Our eyes have a .............. lens whose ......... can be changed at will with the action of ...... muscles.

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A person who can see distant objects clearly but cannot see near objects clearly is said to be myopia

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A person who can see near objects clearly but cannot see clearly the distant objects is called hyperopia

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A photographic camera contains a ........... lens of ...... focal length which forms a.............. image of the object on the light sensitive film.

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The lens used in spectacles for the correction of short sightedness is a

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The image formed by convex lens in a simple microscope is ...... erect and ...........

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A telescope gives an .............. (inverted / erect) and ........ (enlarged/diminished) image of a distant object. Choose the correct alternative.

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A ...... lens is used to correct myopia and a ........ lens is used to correct hypermetropia.

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Both the lenses used in a telescope are

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Fill in the blanks:
The space between the cornea and the eyes lens is filled with a liquid called ___________ .

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Fill in the blanks:
The space between the lens and the retina is filled with a liquid called __________ .

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The least distance of distinct vision is

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The light enters our eye through the transparent _________, passes through the _______ and is focused on the _______. The ________ is sensitive to light and sends images to our brain through  _________ . 

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Fill in the blacks with the correct words to make true statements:
Near sightendness and far sightedness happen when light is not focussed on the ...............

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Fill in the blacks with the correct words to make true statements:
The amount of light entering a camera depends on the size of the aperture and the time of ..............

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The ability of the lens in human eye to change the power of the lens to be able to see the near and far off distances is called the power of

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State whether true or false :
A camera produces a real, inverted and diminished image.

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State whether true or false :
A projector produces a real, inverted and magnified image.

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State whether true or false :
When a convex lens is used as a magnifying glass (simple microscope), a real, inverted and enlarged image is produced.

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State whether true or false :
In a photographic camera, a convex lens of larger focal length is used.

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State whether true or false : 
Our eyes have a convex lens whose focal length can be changed at will by the contraction and relaxation of cilliary muscles.

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State whether true or false :
A concave lens is used as a magnifying glass

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State whether true or false :
Both the telescope and compound microscope make use of two lenses-one concave and one convex.

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You are given two convex lenses of focal lengths 5 cm and 25 cm. Which one of these would you like to use as an objective in a telescope? Give reasons for your answer.

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What is the name of the convex lens at ?

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What is lens called ?

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How did the rishi explain the different ways in which the two birds behaved?

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Which lens has the greater in the focal plane of which lens ?

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Look at the figure and answer the following question:
Is the final image in the diagram real or virtual ?

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L

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Identify the part "D" from the shown figure of human eye : 

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Identify the part "C" from the shown figure of human eye :

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Identify the part 'A' from the shown figure of human eye :

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Identify the part "B" from the shown figure of human eye :

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Identify the part "E" from the shown figure of human eye : 

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Which part of human eye controls the amount of light entering the eye?

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What is the name of the circular aperture through which light enters the eye ?

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Which of the lenses of a compound microscope has the shorter focal length ?

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The final image formed by a compound microscope is inverted:

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What is the distance x, in centimeters, for a person with normal vision ?

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Identify the defect in the eye shown in the figure.

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Identify the defect shown in the image.

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Identify the defect which is corrected in the attached figure.

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The figure illustrates correction of vision for a certain defect of human eye. Identify the defect which is corrected here.

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What is meant by power of accommodation of the eye ?

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What is the far point and near point of the human eye with normal vision ?

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A student has difficulty in reading the blackboard while sitting in the last row. From the given options, choose the defect child is suffering from and its correction measures :

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Why is a normal eye not able to see clearly the objects placed closer than 25 cm

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What happens to the image distance in the eye when we increase the distance of an object from the eye ?

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Blind spot refers to the : 

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Sometimes, a person suffers from both the defects, myopia and hypermetropia. Which of the following is used to correct this defect?

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Which of the following is not an advantage of having two eyes?

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If there are two converging lenses in a compound microscope, why is the image still inverted ?

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What is the function of the iris in human eye ?

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For how long (approximate value) does the image remain on the retina?

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How are we able to see a moving picture ?

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State two similarities between a human eye and a camera

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Compare human eye with a photographic camera

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In telescopes, at least two converging lenses are used: one for the objective and one for the eye piece. These lenses must be positioned in such a way that the final image is virtual and very much enlarged. In terms of the focal points of the two lenses, how must the lenses be positioned ?

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Tarun wears spectacles having convex lenses. When he tries to read a book by keeping it at a distance of 25 cm, the text print seems to be blurred. Is the image of the text formed before the retina or beyond the retina ?

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Tarun wears spectacles having convex lenses. When he tries to read a book by keeping it at a distance of 25 cm, the text print seems to be blurred. What conclusion can be drawn about the least distance of distinct vision of Tarun's eye ?

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Hema viewed a certain object and found that it is not clearly visible to her. It was found that the image was formed by his eye lens away from the pupil of his eye.
Hema can correct this defect in her vision by using:

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With age 'Near point' and 'Far point' recedes due to
A. Weakening of ciliary muscles
B. decreasing ability to change the focal length

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In a healthy human eye, the focussing is done by the

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A person who is nearsighted will have the most trouble in reading:

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Which of the following parts of the eye refracts light ?

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A vision problem that happens when light is focussed in front of the retina is:

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A simple telescope has

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The power of a microscope lens is the amount of magnification the lens gives. For example, a 10 X lens magnifies objects 10 times. How many times is an object magnified if it is viewed with both a 5 X lens and a 30 X lens ?

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The lens used in spectacles for the correction of short-sightedness is a 

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The image formed by convex lens in a simple microscope is

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The type of lens present in human eye is

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What type of lens from the following would you have in your magnifying lens to read a page in small print ?

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Fill in the blanks:
The power of accommodation in a human eye is the ability of the (i)____ to adjust its (ii)___.

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Match the items given in A, B, C and D against their corresponding description given in 1, 2, 3, 4 and 5.
A. Astronomical telescope
B. Galilean Telescope
C. Simple Microscope
D. Compound Microscope

1. Contains one convex lens
2. Contains one concave lens
3. Contains a convex lens of large focal length in the objective and a convex lens of small focal length in the eye-piece
4. Contains a convex lens of small focal length in the objective and a convex lens of large focal length in the eye-piece
5. Contains a convex lens of large focal length in the objective and a concave lens of small focal length in the eye-piece. 

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Bi-focal lens are required to correct :

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When light rays enter the eye, most of the refraction occurs at the

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A man cannot see objects distinctly at a distance less than 1 metre. He is suffering from 

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How should a man wearing spectacles work with a microscope ?

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For a telescope, the focal lengths of two lenses are 30 cm and 10 cm. One acts as objective and the other as eye-piece. The length of the telescope is

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The magnifying power of a compound microscope can be increased by

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We cannot see the details of a distant object because

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Quantity of light entering the eye is controlled by

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A student finds the writing on the blackboard to be blurred and nuclear when he sits in the front row at an approximate distance of 2 m from the black board. Draw ray diagram to illustrate the formation of image of the writing on the blackboard by his eye-lens when he is seated in the
(i) last row
(ii) front row

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Cinematography makes use of 

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Match List-I with List- II and select the answer using the codes given below the lists:

List-IList-II
A.Microscope1.To see objects on the surface by an observer in a trench
B.Telescope2.To see small objects
C.Periscope3.To see distant objects
D.Camera4.To take photographs of objects

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In a motion picture, the consecutive frames are almost the same and quickly switched.

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Solve the following crossword with the help of the given clues:
Across
(1) A microscope consisting two convex lenses
(3) The jelly-like substances that fills the area of the eyeball between the retina and the lens.
(5) A lens mounted in a frame used to make an object appear layer than it really is
(7) The organ of the body with which humans are able to see
(9) The clear, watery fluid that fills the chamber of the eye between the cornea and the lens.
(11) An optical instrument used to view distant objects. It makes far away objects appear larger when viewed through it.
(12) Defect of human eye, by virtue of which a person can see clearly the distant objects but we the nearby objects.
Down
(1) The front transparent part of the eye that is bulged outwards. Light from objects enter the eye through it.
(2) An optical device consisting of a conve lens of small focal length that is used to make things.
(4) An apparatus for taking photographs.
(6) The flat-coloured membrane in the lens that contacts the size of the pupil
(8) The opening in the centre of the iris through wheels light enters the eye.
(10) The defect of human eye due to which a person is able to near objects at close range better than distant objects.

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Self Assessment Sheet - 7

28 Qs

Related questions

Match Correctly:

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Which of the following are defects of vision?

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List three optical instruments, and describe what they do ?

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What are the characteristics of the final image formed by a magnifying glass ?

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What are the characteristics of the final image formed by a telescope ?

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What are the characteristics of the final image formed by a compound microscope ?

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Compare the focussing in a camera with the focussing in a human eye.

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Explain how the eye adjusts itself when a person enters a dark cinema hall from bright sunshine.

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The human eye can focus objects at different distances by adjusting the focal length of the eye.
This is due to:

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The human eye forms the image of an object at its

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The least distance of distinct vision for a young adult with normal vision is about

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The change in focal length of an eye lens in human eye is caused by the action of the:

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What type of image is produced by the cornea and the lens on the retina ?

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What type of image, virtual or real, will be produced when an object will be located inside the focal length of a camera lens ?

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What type of image, virtual or real, will be produced when an object is located outside the focal point of a camera's viewfinder ?

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Draw a diagram to show how hypermetropia is corrected.

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Explain myopia with the help of a ray diagram.

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Draw a concept map using the following terms.

(lens, real image, virtual image, optical instrument, camera, microscope, telescope)

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How does the defect of myopia arise in a human eye?

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The eyeball is approximately  spherical in shape. What is the diameter of a normal human eyeball?

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What is the far point of a normal human eyes ?

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Fill in the blanks:
An aged person suffering from __________, caused by the weak accommodation power of the eye lens associated with old age, should wear _________ lenses.

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What gives a perception of depth or three dimensional vision to human eye ?

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Retina in a human eye acts like a:

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The image formed as the retina of the human eye is :

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If a person cannot see an object clearly when it is placed at about 25 cm away from him, he is suffering from:

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Cornea is a part of which of the following organs of human body ?

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Choose the correct options.

Having two eyes facilitates in: 

A. Increasing the field of view 

B. Giving 3 dimensional view 

C. Developing the concept of distance / size.

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Question Bank - 10

96 Qs

Related questions

What will be the magnetic field at a distance r when an electric current flows through these things ?

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What is the polarity at the end X of this coil ?

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The strenght of an electromagnet depends on the strenght of the .......... flowing through it and the number of .......... if the wire.

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Which end is a north pole - X or Y ?

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A .......... is a substances that has both attractive and directive properties.

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Why was everyone delighted to see the iron chest on the camel’s back?.

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Who visited the shepherd one day and why?

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Fill in the blanks :
A .......... increases or decreases the voltage of alternating current.

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.......... is the process of making an electric current by changing a magnetic field.

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Study involving both electricity and magnetism is called ______.

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A current is induced in straight wire when it is moved _________ to the magnetic field.

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An electric current which changes its direction (i.e. polarity) after a certain fixed intervals of time is called .......... current.

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Constant magnetic field in the coil induces _________ current in it.

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Electromagnetic induction is the phenomenon of converting .......... energy into electrical energy.

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Look at the solenoids and electromagnets shown below. Identify which of them has the strongest magnetic field and which has the weakest magnetic field. Explain your reasoning.

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Match the statement given in column I to the related description given in column II

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An electric motor converts mechanical energy into electrical energy.

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An electrical generator works on the principle of electromagnetic induction.

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The field lines at the centre of a long circular coil carrying current will be :

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 Magnetic field represented by parallel and equidistant field lines are:

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A permanent magnet is made of steel and loses its magnetism easily. Explain it.

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State whether given statement is True or False
An alternating current cannot be used for electroplating.

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Sushant wins a hand-powered flashlight as a prize in a science fair. The flashlight has a clear plastic case, so he can look inside to see how it works. When he presses the handle, a grey ring spins between two coils of wire. The ends of the wire are connected to the light bulb. So, when he presses the handle, the light bulb glows.
Explain how an electric current is produced to light the bulb.

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Why does a magnetic needle show a deflection when brought close to a current carrying conductor?

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A wire bent into a circle carries current in an anticlockwise direction. What polarity does the face of the coil exhibit ?

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Draw a simple sketch of a step-up transformer. Label the different parts in the diagram.

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State two factors on which the strength of an induced current depends.

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When a solenoid that is carrying current is freely suspended it comes to rest along a particular direction. Why does this happen ?

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What will happen to a compass needle when the compass is placed below a wire and a current is made to flow through the wire ?
Give a reason to justify your answer.

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What energy conversion takes place during the working of a d.c motor ?

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The magnetic field of an electromagnet may be hundreds of times stronger than the magnetic field of just the solenoid. Explain, why ?

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Why does a current-carrying wire cause a compass needle to move ?

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What happens to the magnetic field of an electromagnet if you increase the current in the wire ?

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The shepherd hadn’t been to school because
  • he was very poor.
  • there were very few schools in those days.
  • he wasn’t interested in studies.
Choose the right answer.

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What is the relationship between an electric current and a magnetic field ?

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A transformer works on the principle of :

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Can a transformer work when it is connected to d.c. source ?

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You are sitting in a room in which a strong magnetic field is directed from your left towards right. A beam of electrons is directed from front towards you. What would be the direction of magnetic force on this beam ?

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Explain Oersted's 1820 discovery.

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Explain why rotating either the coil or the magnet in a sgenerator induces an electric current.

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Why an armature of an electric motor rotate ?

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What energy change happen in an electric generator ?

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Name two ways a magnetic can induce an electric current in a wire.

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What is the main differences between a step-up transformer and a step-down transformer ?

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State the function of split ring in d.c. motor.

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Compare a step-up transformer with a step-down transformer based on the number of loops in the primary and secondary coils.

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A transformer has 800 loops in its primary coil and 8,000 loops in its secondary coil. What would be the voltage in the primary coil if the voltage in it secondary coil is 20,000 V.

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Which material is used for making the armature of an electric bell?

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In electric bells, electrical energy transform into ............. energy.

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Which bell terminal is connected to battery terminal C ?

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What is the missing label at ?

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Explain why the deflection occurs in the galvanometer.

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The diagram below show a coil connected to a centre zero galvanometer . The galvanometer shows a deflection to the right when the -pole of a  powerful magnet is moved to the right as shown. Does the direction of the current in the coil appear clockwise or anticlockwise viewed from this end ?

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State the observation in when the coil is moved away from .

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State the observation in when, both the coil and the magnet, are moved to the right at the same speed.

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The figure shows a circuit containing a coil wound over a long and hollow thin tube. Copy the diagram and show the polarity required by each face of the solenoid.

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The figure shows a circuit containing a coil wound over a long and hollow thin tube. Draw the magnetic field lines of force inside the coil and also their direction.

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The figure shows a circuit containing a coil wound over a long and hollow thin tube. Mention two methods to increase the strength of the magnetic field inside the coil.

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Sketch magnetic lines of force around a current carrying coil.

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Figure shows a small bar magnet falling freely through a horizontal coil. Will there be any induced current in the coil ? If your answer is yes, find the direction of induced current.

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Two bar magnets are placed side by side by side that the north pole of one magnet is next to the south pole of the other magnet. If these magnets are then pushed toward a coil of wire, would you expect an emf to be induced in the coil. Explain your answer.

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It is commonly believed that the earth's magnetism is due to the 

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The magnetic field of a solenoid can be increased by 

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A magnetic field cannot exert any force on a :

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To make an electromagnet, the best material which should be used is

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What do you end up with if you cut a magnet in half ?

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A dynamo 

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Which of the following correctly describes the magnetic field near a long straight wire ?

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A pair of transformer is connected in series, as shown in the figure.

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A source of a magnetic field is

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Which metal is used to make ferromagnets ?

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Which of the following actions will decrease the strength of the magnetic field of an electromagnet ?

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In the region around a magnet in which magnetic forces act exists 

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When a charged particle moves perpendicular to a magnetic field, then

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Magnetic field lines

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The magnetic field inside a long straight solenoid carrying current:

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A current is passed through a straight wire. The magnetic field established around it has its lines of forces :

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Electromagnets are used in

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An electric predominantly produces .......... field around it

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An electric fans has an electric motors inside to change:

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The phenomenon of electromagnetic induction is

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For the coil shown in the figure what must be done to induce a clockwise current ?

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A rectangular coil of metallic wire is rotated in a magnetic field. The direction of the induced current changes once in each:

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The force of repulsion between two parallel wires is when each one of them carries a certain current I. If the current in each is doubled, the force between them would be

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The marked end of a compass needle always points directly to

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When a charged particle particle, moving with a velocity v, is subjected to a magnetic field, the force on it is non-zero. This implies that

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There will be no force between two current carrying wires if currents are

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A coil made of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is kept close to the wire ?

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A coil made of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is pushed into the coil ?

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A coil made of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is withdrawn from inside the coil ?

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A coil made of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is held stationary inside the coil?

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A device that increases the voltage of an alternating current is called a(n)

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A compass needle placed just above a wire in which electrons are moving toward west, will point:

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A copper ring with incomplete loop is held horizontally and a bar magnet is dropped through the ring with its length along the axis of the ring. What is the accleration of the falling magnet ?

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Create a concept map using the following words.
Electromagnetism, Electricity, Magnetism, Solenoid, Electromagnet, Magnet field, Electromagnetic induction, Generators, and Transformers, motors.

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Differentiate between step up and step down transformer.

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Self Assessment Sheet - 10

22 Qs

Related questions

Why did Tansen’s enemies want him to sing the Raga?

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A solenoid of n turns carries current I while another solenoid of same length and of n turns carries current What is the ratio of the magnetic strengths of the two solenoid ?

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A generator or dynamo works on the principle:

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Match the items in List I with the correct choice in List II.

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State one point of similarity and one point of difference between an A.C. generator ans a D.C. motor.

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Why did the other governors grow jealous of the shepherd?

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If a soft iron is placed inside the current carrying coil, what is the name given to the device ?

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Give one use of the electric bell.

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State the differences between a permanent magnet and an electromagnet.

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State whether true or false : 
Soft iron is used in electromagnets because soft iron does not retain magnetism permanently.

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State whether true or false :
An electric current is a stream of moving charges which create a magnetic field whose direction is at right angles to the direction of the current

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State whether true or false :
Magnetic field lines are denser at the middle of the magnet.

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State whether true or false :
The magnetic field lines originate from the south pole and terminate at the north pole of the magnet.

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State whether true or false :
The pattern of the magnetic field around a conductor due to electric current flowing through it depends on the shape of the conductor.

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Match the magnetic field lines given below to the types given on the right side of the conductor

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Which of the following statements is wrong ? Magnetic lines of force

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A moving charge will produce

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What is an electromagnet ? State two ways ways by which the strength of an electromagnet can be increased.

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Draw the magnetic field lines due to a straight wire carrying current.

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State two ways by which the magnetic field of a solenoid can be made stronger.

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What material is used for making the armature of an electric bell ? Give a reason for using this material.

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A straight wire of diameter 1 mm carrying a current of 2 amperes is replaced by another wire of 2 mm diameter. The strength of the magnetic field far away is :

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Question Bank 5

102 Qs

Related questions

The bending of a ray of light as it passes from one optical medium to another is called .......... .

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Refraction of light is caused due to the change in the ______ of light in different media.

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The medium in which speed of light is less is called optically .......... medium and the medium in which speed of light is more is called optically .......... medium.

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In the above figure, LM is the .......... between the media A and B.

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XO is called the .......... ray.

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OY is called the __ ray.

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Which of the angles is the angle of incidence ?

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Which of the angles is the angle of refraction ?

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If the two media are glass and air, which of these is glass?

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The first law of refraction states that the incident and refracted rays are in the same ________ as the normal.

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The second law of refraction states that :

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The second law of refraction is also named after its discoverer as :

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The ratio where and are the angles of incidence and refraction respectively is called the _________ of the second medium (B) with respect to the first medium (A).

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The ratio  is called the .......... of this medium.

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The .......... of a medium gives an indication of the light bending ability of that medium.

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The S.I. symbol for refractive index is r

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What is the angle of incidence if a ray of light is not deviated when it enters a block of glass?

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What is the refractive index of a vacuum?

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When a ray of light passes through a rectangular glass block, the direction of emergent ray is .......... to the incident ray.

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Refractive index of glass = .

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The splitting of white light into its constituent colours by a triangular prism is called ________ .

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The band of colours obtained on a screen on passing white light through a prism is called  _________ .

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The word 'VIBGYOR' is made of the initial letters of the seven colours of the :

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Colours of rainbow are in VIBGYOR sequence:

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Fill in the blanks:
Rainbows are caused by the dispersion of white light in __________.

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It was the British scientist _______who discovered in 1666 that light consists of seven colours. Fill in the blank.

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Angle of deviation is the angle which the ................. ray makes with the direction of ................. ray.

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The light of one single color is called as:

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The second law of refraction states that the incident ray, the refracted ray and the normal at the point of incidence, all lie in the ................ plane.

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If the refractive index of medium with respect to medium and that of medium with respect to medium are given as and respectively, then the refractive index of a medium with respect to a medium can be found by using the relation


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A ray of light traveling from one medium into another:

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, where n denotes the refractive index of a medium, v the speed of light in the medium and c the speed of light in vacuum. The above statement is

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State whether true or false:
The apparent depth of the water in a pond is less than the real depth. 

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State whether given statement is True or False
Light travels at a lower speed in water than in glass.

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State whether true or false:
Light travels in a straight line path while passing through different media.

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State whether the given statement is True or False.
The deviation produced by a prism is independent of the angle of incidence and is the same for all the colors of light. 

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The white light is a monochromatic light. The above statement is

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State whether true or false:
A graph between i and r is a straight line, where 'i' and 'r' are angles of incidence and refraction respectively.

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When white light enters a prism, the blue light will bend

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The angle between the incident ray and the emergent ray in a glass prism is called as

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State whether the following statement is True or False. 
In an optically denser medium, the speed of light is more than the speed of light in air.

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A swimming pool appears shallower than its actual depth due to

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Which of the following phenomena is related to the formation of rainbows?

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When white light passes through a prism, which will be bent more, the red or green light?

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After a storm, a man walks out onto his porch. Looking to the east, he sees a rainbow that has formed above his neighbor's house. What time of day it is?

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When trying to catch a fish, should a pelican dive into the water horizontally in front of or behind the image of the fish it sees?

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H.G. Wells wrote a famous novel about a man who made himself invisible by changing his index of refraction. What would his index of refraction have to be to accomplish this?

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Is the color of emergent beam X white light:

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If a ray of light passes from medium to medium without any change of direction, what can be said about the refractive indices of these media (angle is not zero)?

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 Why did the farmer’s wife strike the mongoose with her basket?

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Why do the planets not twinkle?

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Why does a straight rod appear bent in water?

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A coin kept in a container and not visible can be viewed by pouring water into the container. It happens because of the 

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State true or false:
At dawn or dusk, the sun appears to be above the horizon for three or four minutes longer than it really is.

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Which of the following conditions is not necessary for refraction to occur?

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Which colour of light is most refracted during dispersion by a prism?

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If an object in air is viewed from beneath the surface of water below, where does the object appear to be?

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The unit of refractive index is:

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When a ray of light travels perpendicular to the surface of separation of two mediums, it

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The angle between the incident and the emergent ray from a glass slab is

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While a white light ray, passes through a glass prism, the colour which disperses the least is:

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The angle between the normal and refracted ray is called :

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When light splits after passing through a glass prism into seven colours, the phenomenon is called:

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Rainbow is formed due to:

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When a ray of light undergoes refraction, a straight line graph is obtained by plotting sine of angle of incidence versus sine of angle of refraction. The slope of graph represents

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The setting sun often looks oval in shape because of

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The deviation produced by an equilateral prism, when a ray of light is incident on it, does not depend on :

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Light does not bend while travelling from rarer to denser medium.

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A ray of light passes through a prism as shown in the figure.
The angle is known as :

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The spectrum in which the colors are separated using a narrow source of light is called:

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Which of the following figures correctly represents the passage of white light through a prism ?

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Which of the following sources of light is different from others ?

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Two identical prism PQR and P' Q' R' are given. White light is passed through PQR as shown in fig.
Which of the following position of P' Q' R' will again yield white light ?

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A ray of light falls on three glass slabs of the same material at the same angle of incidence. In which case, is the lateral displacement of the emergent ray of light
(a) maximum
(b) minimum

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A narrow beam of light enters a hemispherical block of glass through the point B to strike at the centre (C) of the block. The ray then emerges out of the block along CD. Why does the beam not suffer refraction when it enters the block at point B, yet it gets refracted at the point C ?

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Two isosceles right angled glass prism are placed near each other as shown in the figure. Complete the path of the light ray entering the first isosceles right angled glass prism till it emerges from the second identical prism.

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The figure shows refraction of a light ray from a glass slab. Write the value of angles x and y. What is refractive index of slab material ?

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A ray of light passes through a right angled prism as shown in the figure. State the angle incidence at the faces AC and BC are and respectively.

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Does the source appear to be nearer or farther with respect to surface AB ?

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How does the shift depend upon the thickness AD or BC of the block ?

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Justify your answer in (ii) with the help of ray diagram.

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For the same rectangular block which colour from the visible spectra will produce the maximum shift ?

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In the figure given below, a ray of light PQ is incident normally on one face AB of an equilateral glass prism. What are the angles at faces AB and AC ?

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The figure shows the path of a ray of light, through a rectangular glass block in a liquid of uniform density.
Does the light speed up or slow down in glass ? Give reason to your answer.

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Which one of the following sums up the story best?
  • A bird in hand is worth two in the bush.
  • One is known by the company one keeps.
  • A friend in need is a friend indeed.

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Why did the farmer bring a baby mongoose into the house?

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What are the things the child sees on his way to the fair? Why does he lag behind?

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What is the relation between angle of incidence i and angle of refraction r in the glass ?

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Trace the path of the reflected and refracted rays.

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Show at least two rays emerging from the surface PQ after reflection from the surface RS.

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How many images are formed in the above case ?
Which image is the brightest ?

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The velocity of light in diamonds is 121000 kms. What is the refractive index ?

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Calculate the velocity of light in a glass block of refactive index . Velocity of light in air =

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A light ray falls on the air glass interface at an angle of . What is the angle of refraction for this rays ?
.

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When a light ray moves from air to a transparent medium the angle of incidence and the angle of refraction are and respectively. Find the refractive index of this medium is

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The depth of water in a bucket is 40 cm but its bottom appears to be raised by 10 cm. What is the refractive index of water ?

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Normally

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A glass block of thickness is placed on a postage stamp. What would be the apparent depth of the stamp if it is viewed. Obliquely above the glass slab ?

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When a container is completely filled with water its bottom appears raised by 4 cm. Find the actual depth of water.

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The figure given below shows a container C partially filled with water. There is a plane mirror M at the bottom of the container. A light ray AB incidents on the surface of water at angle of incidence . Copy and complete the ray diagram. Mark the ray emerging from the water surface. Refractive index of water = .

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A ray of light strikes a glass slab 5 cm thick, making an angle of incidence equal to  . Construct the ray diagram showing showing the emergent ray and the refracted ray through the glass block. The refractive index of glass is 1.5. Also, measure the lateral displacement of the ray. Take .

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The figure given below shows a solid glass block of refractive index . The lower surface of the block is silvered and behaves as a reflecting mirror. white light ray incidents on the glass block at angle of incidence . Copy the diagram and trace the path of reflected and refracted rays from upper and lower surface of the block.

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Self Assessment Sheet - 5

26 Qs

Related questions

Why red light travels fast then violet in transparent medium??

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Fill in the blank.
A rainbow is caused due to the __________ of white light.

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Fill in the blank. 
If c is velocity of light in air or vacuum and v that in a medium, then refractive index (n) =

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State whether true or false :
Lights of all colour travel at the same speed in vacuum.

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State whether true or false :
Sunlight is a polychromatic light

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State whether the following statement is True or False. 
Lights of all color travel at the same speed through any transparent medium.

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In which of the following cases will no dispersion take place when sunlight passes through it ?

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A prism splits a beam of white light into its constituent colours. This is so because .......... of different colours is different.

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Which of the following colour of light undergoes the least deviation while passing through a glass prism ?

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Which of the following correctly represents the graphical variation between very small angles of incidence (i) and refraction (r) ?

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When light travels from one medium into another, it suffers

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Draw a ray diagram to illustrate the bending of a stick in water

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In the diagram given below, label the incident, refracted and emergent rays. Also, indicate the angle of deviation.

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Which of the following figures correctly shown the bending monochromatic light inside the prism ?

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When a ray passes through a prism,

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A ray of light passes through as equilateral glass prism such that the refracted ray inside the prism is parallel to its base. How is the angle of emergence related to the angle of incidence

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The ratio of real depth to apparent depth is called the the

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The angle between two plane refracting surfaces of the prism is called the angle of

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The stars twinkle in the night because:

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State Snell's law of refraction of light.

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In the following figures, mark the correct light as it travels through different medium.

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In the following figure, mark the correct light as it travels through different mediums.

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In the following figures, mark the correct light as it travels through different mediums.

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A coin is placed at the bottom of a tin can. Move your eyes until the coin is just out of sight (see diagram). Keep your eyes in this position while someone pours water gradually into the tin can. What would you observe ? Explain your observation.

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With the help of a well-labelled diagram show that the apparent depth of an object, such as a coin, in water is less than its real depth.

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How is the refractive index of water related to the real depth and the apparent depth of a column of water ?

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Question Bank - 8

186 Qs

Related questions

.......... happens when a wave passes from one medium to another at an angle.

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The bending of a wave around a barrier is called .......... .

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.......... occurs when a light ray bounces back from a barrier.

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.......... happens when two or more waves overlap.

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.......... is a phenomenon that occurs when two objects naturally vibrate at the same frequency and the sound produced by one object causes the other object to vibrate.

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The .......... of a sound depends on its amplitude.

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Sound cannot travel through .......... .

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Vibrations of frequency less than 20 Hz are called ..........

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Sound travels at .......... speed than light.

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Reflected sound waves are called ......... .

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The measure of how high or low a sound is called .......... .

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.......... is unpleasant sound produced by irregular wave patterns.

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Sound is produced by .......... .

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Of the three mediums, solids, liquids, and gases, sound travels fastest in ......... .

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Two different instruments playing the same note sound different because of .......... .

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When a body vibrates, the number of crests and troughs made in a given time is called ......... .

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The maximum displacement of a wave on either side of its mean position is called .......... .

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Sound waves having frequencies more than 20,000 Hz are called .......... .

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A .......... is a disturbance that travels through space or matter and transmits energy.

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The distance between any two successive crests or compressions in a longitudinal wave is called .......... .

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What kinds of sounds have the frequency of 15 Hz ?

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What kinds of sounds have the frequencies of 50 Hz ?

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What kinds of sounds have the frequencies of 600 Hz ?

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What kinds of sounds have the frequency of 1500 Hz ?

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What kinds of sounds have the frequency of 60000 Hz ?

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With the help of the given clues, unscramble the letters to make a meaningful word.
BDECILE (Unit of loudness of sound)

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With the help of the given clues, unscramble the letters to make a meaningful word.
HCEO (A reflected sound wave)

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With the help of the given clues, unscramble the letters to make a meaningful word.
NASRO (A device used in the ship to locate unseen underwater objects)

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With the help of the given clues, unscramble the letters to make a meaningful word.
CNSTURAIOL (Sound with frequency above 20 kHz).

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With the help of the given clues, unscramble the letters to make a meaningful word.
ETHZR (unit of frequency of sound wave)

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With the help of the given clues, unscramble the letters to make a meaningful word.
RAYXLN (produces sound in humans)

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The picture shows a wave generated in a laboratory. The wavelength of the wave is ?

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The picture shows a wave generated in a laboratory. If the frequency of the wave shown were doubled, the wavelength of the wave would become :

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The picture shows a wave generated in a laboratory. What is the amplitude of the wave shown ?

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Match the columns :

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Match the columns :

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Match the columns :

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How do we hear : Match the parts of a human ear with their functions :

Match the columns :

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What kind of wave is this?

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Label the compressions and rarefactions.

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How do vibrations make these kind of waves?

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Look at the waves shown below. Rank these waves from highest energy and explain your reasoning.

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 Which one of the following is the amplitude of the wave?

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The period of vibration of the particle is

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1 Hz is equal to

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Figure (a)  indicates low pitch while figure (b) indicates high pitch.

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Which figure indicates high pitch?

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What kind of sound noise or music is represented by the sound wave shown here.

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The figure given shows the images of sound waves. Look at them and answer the following question. 
Which sound is noise?

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The figure given shows the images of sound waves. Look at them and answer the following question.

Which represents the softest sound?

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The figure given below shows the images of sound waves. Look at them and answer the following questions. Which represents the sound with the lowest pitch?

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The figure given below shows the images of sound waves. Look at them and answer the following questions. Which two sounds were produced by the same instrument?

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Refer to the chart and tell which two animals can make the widest range of sounds?

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Refer to the chart and tell which animal can make a wider range of sounds than what it can hear?

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Refer to the chart and name the animal sounds that man cannot imitate.

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Refer to the chart and explain why a dog whistle can be heard by dogs, but not by man ?

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Refer to the chart below and answer the given questions related to it. Which two animals can make sound with the highest pitch?

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Suppose a person have two choices of buying a house - a roadside house or a house which is few lanes away from the roadside. Which house would you suggest this person should buy?

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Lightning and thunder take place in sky and at the same distance from us. Explain why lightning is seen earlier and thunder is heard later ?

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What devices are used to locate underwater objects and to determine depths of water beneath the ship?

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Do ultrasounds travel faster than we can hear?

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Would the pilot of an airplane breaking the sound barrier hear a sonic boom? Explain why or why not?

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After working in a factory for a month, a man complains about a ringing in his ears. What might be wrong with him ? What do you think may have caused his problem? What can you suggest to him to prevent further hearing loss?

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Sound pulses emitted by dolphin travel through C ocean water at a rate of . In C air, these pulses would travel at 342.9 m/s. How can you account for this difference in speed?

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If a 15 - person musical group has 15 new members, so that its size doubles, will a listner perceive the music created by the group to be twice as loud? Why or why not?

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What is the minimum distance required to hear an echo?

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Explain why a person at a rock concert will not feel gusts of wind coming out of the speakers.

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If you clap on one end of a long steel pipe you will hear two distinct sounds on the other end of the pipe. Explain.

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A time keeper in a 100 m run is advised to start the stop watch by seeing the smoke from the starter's gun and not b hearing the sound of fire. Why?

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Why trains are not allowed to move on a long railway bridge with constant speed?

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In the fair he wants many things. What are they? Why does he move on without waiting for an answer?

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Name the characteristics of sounds which enables a person to differentiate between two sounds with equal loudness but having different frequency.

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Pitch is the characteristics of sound by which an acute note can be distinguished from a grave note.

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Why are musical instruments like the guitar provided with a hollow box?

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What change, if any, would you except in the characteristic of a musical sound when we increase its frequency.

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What change, if any, would you except in the characteristic of a musical sound when we increase its amplitude ?

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A wave has a low speed but a high frequency. What can you infer about its wavelength?

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Why does everything seem so quiet after a snowfall?

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If the wavelength of a sound source is reduced by a factor of 2, what happens to the waves frequency? What happens to its speed?

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Sometimes when a vehicle is driven at a particular speed, a rattling sound is heard. Explain briefly, why this happens and give the name of the phenomenon taking place.

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Suggest one way by which rattling sound could be stopped.

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Will the sound be audible if the string is set into vibrations on the  surface of the moon?

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Two friends blow two whistles at the same time. The first whistle makes a sound whose frequency is twice that of the sound made by the other whistle. Which sound will reach you first ?

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Have you ever sung in the shower ? Why does your voice sound so much better there.

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Why is it sometimes when you play loud music, you feel your body shake.

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Sound travels faster on a rainy day then on a dry day. Why?

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The rear view mirror of a motorbike starts vibrating violently at some particular speed of motorbike. Why does it happen ?

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What is the name of phenomenon taking place ?

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What could be done to stop the violent vibrations ?

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Explain why tsunami are so dangerous. How can scientists predict when tsunami will reach land?

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Your friend is playing a song on a piano. Whenever your friend hits a certain key, the lamp on top of the piano rattles. Explain why the lamp rattles.

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Name two wave interaction that can occur when a wave encounters a barrier.

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Explain why you can hear two people talking even when they walk around a corner.

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How could two waves on a rope interfere so that the rope did not move at all?

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Two musical notes of the same pitch and loudness are played on a violin and a piano. The wave forms are as shown in the figures given below. Explain why the wave patterns are different.

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Suppose you hear music being played from a trumpet that is across the room from you. Compressions and rarefaction from the sound wave reach your car, and you interpret these vibrations as sound. Were the air particles that are vibrating near your ear carried across the room by the sound wave? How do you know?

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The lower, the frequency of vibrations, the higher the pitch. Why?

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Noise pollution may cause deafness. Explain.

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Pleasant sound is termed as music and is produced when vibrations produce waves in regular pattern. Why?

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The frequency of a wave is the number of reasts or throughs that are made in a given time.

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Why was the new governor called to the palace?

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Echoes are the reflected sound waves that we hear. Explain.

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The loudness level of a whisper is around 15 decibels. Explain.

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Musical sound is produced by periodic vibrations.(True/False)

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A ticking clock sounds less when heard through a metal.

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Sound tends to travel faster at higher temperature of the medium.

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State whether true or false :
A medium is not necessary for the propagation of sound.

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Justify the statement :
Sound is carried by longitudinal waves.

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Justify the statement :
A non-vibrating body cannot produces sound.

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Time in which the vibrating particle completes one vibration is called the time period. Explain.

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Quality of two different string instruments cannot be the same. Explain.

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State whether the given statement is True or False :
Besides medium through which sound is traveling, the temperature also affects the speed of sound.

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State whether the given statement is True or False :
If a pebble is thrown into the water the ripples on the surface of water are created due to translatory motion of the water particles.

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State whether true or false:
Velocity of wave propagation = frequency wavelength 

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If the distance between two successive crests of a wave is 14 cm, the distance between two successive troughs is 7 cm.

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State whether given statement is True or False :
Sound travels faster in vacuum than in air.

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In the following properties of a wave, the one which is independent of the other is

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When longitudinal wave propagates through a medium, then the physical quantities propagating in the direction of wave are

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Fill in the blank.
On vibrating, the arms of a tuning fork produces ________  in air.

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During propagation of longitudianl wave, if at any time, there is compresion at a point, after how much time there will be rarefraction ?

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Which of the following results in more energy in a wave ?

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The combining of waves as they overlap is known as

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A supersonic plane flies mat the speed

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A train, blowing a whistle of frequency , is standing in the railway yard. A person is running towards the engine. The frequency of the sound of the whistle as heard by the personn will be

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A veena player compares with a tuning fork the fundamental frequency generated by one of the strings of the veena and hears 4 beats/s. He then tightens the string a bit and hears only 3 beats/c. Then 

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Intensity of sound at a point is_______ its distance from the source.

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Sound travels with difference speed in different media. In what order does the velocity of sound increase in these media ?

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The frequency vibration of a stretched strings is ______length. Fill in the blank. 

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The fundamental characteristics of all waves are

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The velocity of sound in air increases by about ______ for in temperature. Fill in the blank.

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The velocity of sound in gas is independent of _______. Fill in the blank.

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The velocity of sound is________ the density of the medium. Fill in the blank.

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When a tunning fork produces sound waves in air, which one of the following is the same in the material of tunning fork as well as in air ?

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What are ultrasonic waves ?

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In hich of the following medium the velocity of sound will be maximum ?

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Sonar is a device for

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Transverse waves cannot travel through

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Sound is form of

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In a solid rod the sound waves will be

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Under similar conditions, in which of the following gases will the speed of sound be the least ?

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When mechanical waves have a frequency below the audible range, these are called

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Which of the following parameters determines the loudness of sound ?

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Which of the following statements is not true about a sound wave ?

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Which of the following parameters of a wave undergoes a change when wave is reflected from a boundary ?

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Which of the following factors change when a sound gets louder?

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Which changes when a pitch gets higher ?

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The characteristics of sound which enables us to distinguish two musical sounds coming from different sources but having the same frequency and loudness is :

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Microphone is used to convert

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The velocity of sound at and 380 mm pressure is 340 m/s. If the temperature remains constant and pressure is doubled, the velocity of sound will be

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Which of the following properties of sound is affected by change in air temperature ?

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Two vibrating systems are in resonance when

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In a pipe open at both ends the fundamental note is produced when its length is equal to

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A normal man is unable to hear the sound emitted by source. Out of the possible reasons, the one which is not applicable is

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Which of the following statement is true ?

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If the ratio in the amplitudes for two waves of equal frequencies is 1 : 3 then the ratio of the energies carried out by the waves will be

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A bell ringing in an evacuated jar cannot be heard.

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The flash of lightning is seen before the sound of thunder is heard.

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The thickest string in a musical instruments gives the highest noise

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What is the frequency of a wave if 3 waves are produced in half second?

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What is the wavelength if the distance between a crest and immediate trough in a transverse wave is 15 m?

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Find the velocity of a wave whose frequency is 60 Hz and wavelength is 20 m.

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What is the wavelength of a transverse wave if the distance between the 1 st crest and the third crest is 8 m?

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What is the wavelength of a longitudinal wave if the distance between the 5th rarefaction and the 6th rarefaction is 25 cm?

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What is the wavelength if the time period of a wave is 1 millisecond and the velocity of the wave is 330 ms?

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Frequency of a sound wave if it travels with a speed of 330 ms in air and the wavelength of the wave is 330 cm is :

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Time period of a wave if 10 waves are produced in 4 s.

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Distance between the 1st compression and the fifth subsequent rarefaction in a longitudinal wave if the wavelength of the wave is 20cm.

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Time taken to complete 6 successive compressions if the time between two successive compressions of a wave is 4 sec is :

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The time period of a wave if the time interval between 1st crest and 9th crest is 48 s.

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The velocity of sound in a gas is 4 times that in air at the same temperature. When a tuning fork is sounded in a wave of frequency 480 and wavelength is produced. The same fork is sounded in the gas and of is the wavelength of the wave, then is :

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Sound travels with a speed of about 330m/s. What is the wavelength of sound whose frequency is 660 Hz?

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Find the time period of a wave those frequency is .

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A source is producing 20 waves in 4 sec. The distance between a crest and a trough is 12 cm. Find the frequency.

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The velocity of the wave

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A body is vibrating 7200 times in one minute. If the velocity of sound is 360 m/s, find (i) frequency of the vibration in Hz, (ii) the wavelength of the sound produced.

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A ratio station transmists musical programme at 220 m wavelength and 1200 Hz frequency. Calculate the velocity of radio waves.

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A longitudinal wave is travelling along a spiral spring with a velocity of 2 m/s. if the period of the wave is 0.2 s, find the wavelength.

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In a ripple tank,15 full ripples are produced in one second. if the distance between a trough and the next crest is 20 c.Calculate frequency

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Wavelength

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In a ripple tank,15 full ripples are produced in one second. if the distance between a trough and the next crest is 20 c.Calculate velocity of the wave.

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A boat at anchor is rocked by waves whose trough are 80 m apart and whose velocity is 20 m/s. how often do the crest the boat ?

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A radio station transmits waves of wavelength 400 m. If the speed of the waves is , Find the frequency of the radio station.

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A submarine that is not moving sends out a sonar sound wave travelling at 200 m/s, which reflects off a boat back to the submarine. The sonar crew detects the reflected wave 8 s after it was send out. how far away is the boat from the submarine?

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A body shouts inside a deep well and hears the echo 0.4 s after shouting. if the speed of sound is 340 find the depth of the water level in the well :

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A boy standing between two cliffs claps and hears 2 echoes after 2s and 2.5 s respectively. If the velocity of sound is 330 , find the distance between he two cliffs :

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