Question

calculate the work done is moving a charge of 3 coulomb from O point where potential is 20 volt to another point where potential is 40 volt?

Answer 1

Potential Difference between two points can be defined as the work done to bring a unit charge from one point to the other.

So let the point A have potential 20V and point B have potential 40V.
Potential Difference = 40V-20V = 20V

And, Potential Difference = Work Done per charge
so, 20V = Work / 3C
      60J = Work Ans