Question

Express power in terms of force and velocity. Write down the expression of the potential energy stored in a​

Answer 1

Explanation:

Let us consider a capacitor of capacitance C and potential difference V between the plates.

Let the charge on one plate be +q and -q on the other.

Suppose the capacitor is being charged gradually.

Now,at any stage the charge on capacitor is q.

Therefore, the potential difference =

C

q

Small amount of work doe in giving n additional charge dq to the capacitor is

dW=

C

q

∗dq

Total work done in giving a charge Q to the capacitor is

W=∫dW

W= ∫

0

Q

C

Q

dq

W =

C

Q

2

Energy = E

E=

2C

Q

2

=

2

CV

2

=

2

QV

The energy is stored in the form of potential energy.