Question

When 3 volts e.m.f. is applied across a 2-farad capacitor, it will store the energy of​

Answer 1

Given:

3 volts e.m.f. is applied across a 2-farad capacitor,

To find:

Energy stored in the capacitor.

Calculation:

General expression for energy stored in a capacitor in terms of potential difference and capacitance is :

$\boxed{ \sf{E = \dfrac{1}{2} C {V}^{2} }}$

Putting available values in SI unit ;

$= > \sf{E = \dfrac{1}{2} \times 2 \times {(3)}^{2} }$

$= > \sf{E = \dfrac{1}{2} \times 2 \times 9 }$

$= > \sf{E = \dfrac{1}{ \cancel2} \times \cancel2 \times 9 }$

$= > \sf{E = 9 \: \: joule}$

So, final answer is:

$\boxed{ \large{ \red{ \rm{Energy \: stored = 9 \: \: joule}}}}$