Question

(a) In an electric field the work done in bringing a charge of 2 C from
infinity to a point A is 10J and bringing the same charge from infinity to
another point B is 40 J.Find the potential difference between A and B.
Also calculate the amount of work done to move a charge of 6C directly from A to B.​

Answer 1

Explanation:

Given :-

Work done = 10 joule

Charge =  2 Coulomb

Potential of point A = V(a) = 10 J/2 C = 5 V

Given :-

Work Done = 20 Joule

Charge = 2 coulomb

Potential of Point B = V(b) = 20 J/2 C = 10 V

Solution :-

Potential Difference between Point A and B = V(a) -  V(b)

⇒ Potential Difference between Point A and B = 10 V - 5 V

⇒ Potential Difference between Point A and B = 5 V

Now, Work done directly from A to B,

Work Done = Potential Difference × Charge

⇒ Work Done = 5 V × 2 C

⇒ Work Done = 10 Joule

Hence, the potential difference between two points A and B is 5 V and the work done if the same charge is brought directly from A to B is 10 Joule.