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Q: An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and receiving of the wave is 1.6 s. What is the depth of the sea, if the velocity of sound in the seawater is 1400 m/s?

Let, the Depth of sea is x, Distance traveled by sound wave=2d, Time is taken by sound to travel both ways=1.6s, Speed of the sound \$ = \dfrac{total \ distance \ travelled}{ time \ taken } = 1400m/s=\dfrac{2d}{1.6s}\$\$ d=1120m\$

Q: A submarine emits a sound pulse, which returns from an underwater cliff in \$1.02\ s\$. If the speed of sound in salt water is \$1531\ m/s\$ how far away is the cliff?

Speed of sound in sea water, \$v = 1531\ m/s\$.Distance travelled by sound pulse \$= 2\times depth \ of \ sea = 2d\$.Here \$d\$ means depth of sea We know that, \$distance = speed \times time\$Hence,\$2d = Speed\ of\ sound \times time\$\$= 1531\ m/s \times 1.02\$\$= 1561.62\ m\$\$d = \dfrac{1561.62}{2} = 780.81\ m\$.Hence, the cliff is \$780.81\ m\$ away from the submarine.

Q: A sonar device on a submarine sends out a signal and receives an echo \$5s\$ later. Calculate the speed of sound in water if the distance of the object from the submarine is \$3625\ m\$.

We know that, \$ Speed = \dfrac{Distance}{time}\$Time \$= 5 s\$Distance \$= 3625\$ mTotal distance to be travelled by sound \$= 2 \times 3625\$, as it is the distance taken by sonar wave to transmit and receive \$ = 7250\$ mSo, Speed \$=\dfrac{7250}{5} = 1450 m/s\$

Q: Explain the working and application of a sonar.

Working: Sonar consists of transmitter and a detector and is installed in a boat or a ship as shown in Fig. The transmitter produces and transmits ultrasonic waves. These waves travel through water and after striking the object on the seabed, get reflected back and are sensed by the detector.The detector converts the ultrasonic waves into electrical signals which are appropriately interpreted. The distance of the object that reflected the soundwave can be calculate by knowing the speed of sound in water and the time interval between transmission and reception of the ultrasound. Let the time interval between transmission and reception of ultrasound signal be tt and the speed of sound through sea water by vv. The total distance, 2d2d travelled by the ultrasound is then, 2d=vxt2d=vxt.Applications : The sonar technique is used to determine the depth of the sea and to locate underwater hills, valleys, submarine, icebergs, sunkenship etc.

Q: Which of the following type of waves is used in the SONAR device?

Answer is D.SONAR is the best example that illustrates how a ship on the ocean utilizes the reflecting properties of sound waves to determine the depth of the ocean. A sound wave is transmitted and bounces off the seabed. Because the speed of sound is known and the time lapse between sending and receiving the sound can be measured, the distance from the ship to the bottom of the ocean can be determined. This technique is called sonar (SOund Navigation And Ranging).A common use of ultrasound is in SONAR. Ultrasonic waves are used in SONAR instead of audible sound waves.

Q: Ultrasonic signal sent from \$SONAR\$ returns to it after reflection from a rock after a lapse of \$1\, s\$. If the velocity of ultrasound in water is \$1600\, m/s\$, the depth of the rock in water is

If \$ d \$ is the distance of rock from SONAR then,The distance covered by the sound wave is:\$2 d= v t \$\$\Rightarrow d=\dfrac{v \times t}{2}\$\$=\dfrac{1600 \times 1}{2}=800 \ \mathrm{m}\$

Q: A sonar device on a submarine sends out a signal and receives an echo 5 s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m :

The speed of the sound, distance traveled and the time taken relationship if the sound is a reflected sound, that is echo, it is given as follows.\$Speed\quad of\quad sound=\dfrac { 2\times Distance\quad traveled\quad (m) }{ Time\quad taken\quad (s) } \$.In the question it is given that distance traveled by the sound from the object to the submarine is 3625 meters and the time taken to hear the echo is 5 seconds.The speed of the sound wave is calculated as follows.\$v=\dfrac { 2\times 3625\quad m }{ 5\quad s } \$.Hence, the speed of the sound is 1450 m/s.

Q: On sending an ultrasonic wave form a ship towards the bottom of a sea, the time interval between sending the wave and receiving it back is found to be 1.5 s. If the velocity of wave in sea water is 1400 \$ms^{-1}\$ find the depth of the sea.

As the speed of sound in seawater is 1400 m/s in the question, the distance travelled by sound(ultrasonic wave from the ship) in 1.5 seconds is calculated from the formula \$Distance\ traveled=velocity\ of\ sound\times time\ taken\$. That is, \$Distance = 1400 m/s\times 1.5 s\$ \$= 2100 m. \$This is twice the minimum distance between a source of sound (ship) and the reflector (sea bed) as it is reflected sound. So, the sea bed is at a distance of 1050 m at least from the ship. Therefore, the depth of the sea is 1.05 km.

Q: An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and receiving of the wave is 1.6 s. What is the depth of the sea, if the velocity of sound in the seawater is 1400 m/s?

Given,Velocity, \$V=1400\,m/s\$Time \$t=1.6 \ s\$Depth of the sea \$d = ?\$In 1.6 sec, the sound wave travels from the ship to the bottom of the sea and then comes back to the ship because of the reflection by the sea bed. Thus the distance covered by the sound wave is twice the depth of the sea.\$\therefore \text {distance} = 2 \times \text {the depth of the sea} (d)\$We know\$\text {Distance} = \text{speed} \times \text{time}\$\$\Rightarrow 2d=V\times t\$\$\Rightarrow d=\dfrac{1400\times 1.6}{2}\$\$\Rightarrow d =700\times 1.6 = 1120 \space m \$\$\therefore\$ option A is correct.

Physics

definition

SONAR

SONAR (Sound navigation and ranging) is a method used in submarines and ships to detect far away objects and obstacles in water. It is based on the principle of reflection of ultrasound waves. It has various applications like echo depth sounding (to find the depth of the sea), detecting enemy submarine etc.
Distance (d) of an object can be obtained as:

d = v t / 2

where v is speed of ultrasound and t is the time between sending the ultrasound and receiving its echo.

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An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and receiving of the wave is 1.6 s. What is the depth of the sea, if the velocity of sound in the seawater is 1400 m/s?

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SONAR

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SONAR

An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and receiving of the wave is 1.6 s. What is the depth of the sea, if the velocity of sound in the seawater is 1400 m/s?

A submarine emits a sound pulse, which returns from an underwater cliff in 1.02 s. If the speed of sound in salt water is 1531 m/s how far away is the cliff?

A sonar device on a submarine sends out a signal and receives an echo 5s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m.

Explain the working and application of a sonar.

Which of the following type of waves is used in the SONAR device?

Ultrasonic signal sent from SONAR returns to it after reflection from a rock after a lapse of 1s. If the velocity of ultrasound in water is 1600m/s, the depth of the rock in water is

A ship sends out ultrasound that returns from the seabed and is directed after 3.42s. If the speed of ultrasound through seawater is 1531 m/sec . What is the distance of the seabed from the ship ?

A sonar device on a submarine sends out a signal and receives an echo 5 s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m :

On sending an ultrasonic wave form a ship towards the bottom of a sea, the time interval between sending the wave and receiving it back is found to be 1.5 s. If the velocity of wave in sea water is 1400 ms−1 find the depth of the sea.

An ultrasonic wave is sent from a ship towards the bottom of the sea. It is found that the time interval between the sending and receiving of the wave is 1.6 s. What is the depth of the sea, if the velocity of sound in the seawater is 1400 m/s?

A submarine emits a sound pulse, which returns from an underwater cliff in $1.02 s$ . If the speed of sound in salt water is $1531 m / s$ how far away is the cliff?

A sonar device on a submarine sends out a signal and receives an echo $5 s$ later. Calculate the speed of sound in water if the distance of the object from the submarine is $3625 m$ .

Ultrasonic signal sent from $S O N A R$ returns to it after reflection from a rock after a lapse of $1 s$ . If the velocity of ultrasound in water is $1600 m / s$ , the depth of the rock in water is

A ship sends out ultrasound that returns from the seabed and is directed after $3.42 s$ . If the speed of ultrasound through seawater is $1531$ m/sec . What is the distance of the seabed from the ship ?

On sending an ultrasonic wave form a ship towards the bottom of a sea, the time interval between sending the wave and receiving it back is found to be 1.5 s. If the velocity of wave in sea water is 1400 $m s^{- 1}$ find the depth of the sea.