The energy stored in a capacitor of capacitance 5μF is 40J. Calculate the voltage applied across its terminals?

A. 4000V
B. 200V
C. 16V
D. 6V
E. 4V

Correct Answer:

Option A – 4000V

Explanation 

E=CV²/2

V²=2/EC

V²= (2×40)/(5×10^−6)

V²=16×10^6

V=4×10³=4000v