Question

In a electric field the work done in bringing a 2 coulomb charge from point (A) is 10 joule and bringing the same charge from point (B) is 20 Joule find the potential difference between two points (A) and (B). what will be the what would be the work done if the same charge is brought directly from (A) to (B).

Answer 1

Work done = 10 joule

Charge = 2 coulomb

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

Given work done = 20 Joule 

Charge = 2  coulomb

Potential of point B= V/B = 20 J / 2C = 10V

Potential differences between two point A and B is 

V = VB - VA

  = 10V - 5V = 5V

Work done directly from A to B.

Work done = Potential  difference × charge 

                    = 5V × 2C

                    = 10 Joule.

Hope u got it...

Answer 2

According to the Question

Firstly for Point A,

Work done = 10 Joule

Charge = 2 Coulomb

Potential of point A = VA = $\bf\huge\frac{10j}{2c}$

VA = 5 Volt

Now for Point B,

Work done = 20 Joule

Charge = 2 Coulomb

Potential of point B = VB = $\bf\huge\frac{20j}{2c}$

VB = 10 V

Potential difference between A and B

V = VB - VA

10V - 5V = 5V

Work done from A to B

Using Formula we get

Work done = Potential difference × charge

= 5V × 2C

= 10 Joule