An electric field does 14 J of work on a 0.0008 C charge.

Question

What is the magnitude of the voltage change?
Answer in units of V.

The same electric field does 28 J of work on a 0.0016 C charge.
What is the magnitude of the voltage change now?
Answer in units of V.

Answer 1

Force= electric field * charge F = E Q
work = energy change = F *d =E Q d
but E d = voltage change
so work = F * d = V Q
14 = V * 8*10^-4
V = (14/8)* 10^4
second one is twice the numerator and twice the denominator :)