Question

How much work is done in moving a charge of 4 C across two points having a potential difference 12 V?

Answer 1

The amount of charge Q, that flows between two points at potential difference V (= 12 V) is 4 C. Thus, the amount of work W, done in moving the charge is
W = V $\times$ Q
= 12 V $\times$ 4 C
= 48 J.