Suppose we take 2 water tanks placed at the same level and fill them with water. We connect both with a tube

Does Water flow from one tank to another?

Answer

No

This is because there is no pressure

 

What if we increase height of one tank. Does Water flow from one tank to another?

Answer

Yes

This is because water now flows from tank having higher pressure to tank having lower pressure

Electric Potential - Teachoo.png

 

Hence, for flow of water, there should be difference in water pressure

Similarly for flow of Electricity, there should be difference in Electricity Pressure

This difference in Electric Pressure is called Potential Difference

 

What is Potential Difference?

The potential difference between two points in an electric circuit

is defined as the work done to Move unit Electric Charge from one Point to another in an electric circuit.

Potential Difference = Work Done/Charge

V = W/Q

 

How is Potential Difference Measured?

It is measured in Volt (V)

It is named after Italian Physicist Alessandro Volta


We Know that

Potential Difference = Work Done/Charge

Since Potential Difference is measured in Volt(V),Work Done in Joule (J) and Charge in coulomb(C).

We can say

1 Volt = 1 Joule/1 Coulomb

1 V = 1 J /1 C

Hence, 1 Volt is amount of potential difference produced when 1 Joule of Work is done to move 1 Coulomb of Charge from One point to another, in an electric circuit.


How is Potential Difference Measured?

It is measured by Device called Voltmeter

It is always connected parallel to points where potential difference is to be measured

Potential difference between two points in an electric circuit can be created with the help of cell or battery.

Circuit diagram to show voltmeter

Voltmeter - Teachoo.jpg

 

Questions

Q1 Page 202 - Name a device that helps to maintain a potential difference across a conductor.

View Answer

 

Q2 Page 202 - What is meant by saying that the potential difference between two points is 1 V?

View Answer

 

 

Q3 Page 202 - How much energy is given to each coulomb of charge passing through a 6 V battery?

View Answer

 

Example 12.2 - How much work is done in moving a charge of 2 C across two points having a potential difference 12 V?

View Answer

  1. Class 10
  2. Chapter 12 Class 10 - Electricity

About the Author

Davneet Singh's photo - Teacher, Computer Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.