Question

A parallel plate capacitor consists of two square parallel plates separated by a distance d. the potential across the plates, while keeping everything else constant, what happens to the energy stored in the capacitor?
A) There will be % of the energy stored
B) There will be % of the energy stored
C) The energy stored will remain constant
D) The energy stored will double
E) the energy stored will quadruple

Answer 1

Answer:

E) the energy stored will quadrupled

Explanation:

The correct question is

A parallel plate capacitor consists of two square parallel plates separated by a distance d. If i double the potential across the plates, while keeping everything else constant, what happens to the energy stored in the capacitor?

A) There will be 1/4 of the energy stored

B) There will be 1/2 of the energy stored

C) The energy stored will remain constant

D) The energy stored will double

E) the energy stored will quadruple

The initial energy stored in the capacitor $E_{i}$ = $\frac{1}{2}CV^{2}$

where C is the capacitance

V is the potential difference

If I double this voltage, while holding every other parameters constant, the new energy stored will be

$E_{n}$ = $\frac{1}{2}C(2V)^{2}$ = $\frac{4}{2}CV^{2}$

$E_{n}$ = $2CV^{2}$

dividing new energy stored by the initial energy stored, we have

$E_{n}/E_{i}$ = $2CV^{2}$ ÷ $\frac{1}{2}CV^{2}$ = 4

the energy stored will be quadrupled.