 # Electric Current and Circuit Diagrams

Electricity has an important place in modern society. What constitutes an electric current? How does it flow in an electric circuit? What are the factors that regulate electric current? Let us study more about it below.

### Suggested Videos         ## Electric Current Definition

An electric current is a flow of particles (electrons) flowing through wires and components. It is the rate of flow of charge. If the electric charge flows through a conductor, we say that there is an electric current in the conductor. In the circuits using metallic wires, electrons constitute a flow of charges.

## Electric Current Formula and Unit

The conventional direction of electric current is taken as opposed to the direction of flow of electrons. If a charge Q flows through the cross-section of a conductor in time t, the current I then I=Q/t. The S.I unit of charge is coulomb and measurement of electric current happens in units of coulomb per second which is ‘ampere’. The current flows from the negative terminal to the positive terminal of the cell. This is a simple electric circuit. It has a lamp, a switch, and a cell.

In a torch, the battery provides the flow of charges which means the bulb in the torch glows due to the electric current. What does a switch do? The switch creates a conducting link between the cell and the bulb. If the circuit breaks, then the current stops flowing immediately and the bulb does not glow.

### What is a flow of current?

When a small amount of electric charge is placed in the electric field due to another charge, it experiences a force. So work has to be done on the positive charge. In electrolytes and ionized gases, both the positively charged ions and negatively charged ions are moving and this constitutes the electric current. If n electrons pass through the cross-section of a conductor in time t, the total charge that passes through the conductor is then,  Q = n×e.

## The schematic diagram represents the different components of a circuit; this is the circuit diagram. These symbols represent the common electrical components. ## Solved Example For You

Q. A current of 0.75 A is drawn by the filament of an electric bulb for 10 minutes. Find the amount of electric charge that flows through the circuit.

Sol: Given, I= 0.75 A, t=10 minutes= 600 s

We know, Q = I× t = 0.75 × 600

Therefore, Q= 450C

Q. What constitutes current in a metal wire?

a. Electrons         b. Protons

c. Atoms              d. Molecules

Sol: a. Electrons. Electric current is the flow of electric charge. The electric charge mainly constitutes the electrons.

Share with friends

## Customize your course in 30 seconds

##### Which class are you in?
5th
6th
7th
8th
9th
10th
11th
12th
Get ready for all-new Live Classes!
Now learn Live with India's best teachers. Join courses with the best schedule and enjoy fun and interactive classes.  Ashhar Firdausi
IIT Roorkee
Biology  Dr. Nazma Shaik
VTU
Chemistry  Gaurav Tiwari
APJAKTU
Physics
Get Started

## Browse

##### Electricity 1 Followers

Most reacted comment
14 Comment authors     Recent comment authors
Subscribe
Notify of Guest
jerry springer

this sucks Guest
Ibrahim

No u are not understanding Guest
sushant

Not to offend no but can u please explain how did you wrote v=i/r when this is completely Wrong . I is proportional to V voltage and this equation is neither true by ohm,s law neither mathematically by manipulating what ohms said. please make this correct. Its a blunder for whosoever is studying especially small students. Guest

Yes. V =IR always true for all the ohmic conductors Guest
Heer

Yea that’s wrong . V=IR Guest
Emmanuel onyedi

Then which one is correct Guest
Sara

V=IR is correct. Guest

Ya bro Guest
Annagrace

🙏 thanks for the correction Guest

For every action theres an equal and opposite reaction so if a circuit is wired for a resistor that has a diode at the other end instead of a transistor would the light bulb make a sound ? Boom .o yeah Guest
Swapneshu Karmakar

What is second law of Ohm on electric currents Guest

Gucci Guest
GUpta

Non linear dependence means Guest
gabe ut secks

My ass hole burns Guest

what is the resistance of the circuit, if the voltage is 12 volts and the current is 6 amperes Guest
sam

2ohms

## Question Mark?

Have a doubt at 3 am? Our experts are available 24x7. Connect with a tutor instantly and get your concepts cleared in less than 3 steps.