Electrostatic Potential and Capacitance

Identical charges (-q) are placed at each corner of a cube of side b then electrostatic potential energy of charge (+q) which is placed at centre of cube will be

1. -4 2q2 0 b
2. -8 2q2 0 b
3. -4q2 3 0 b
4. 8 2q24 0 b

Some charge is being given to a conductor. Then its potential is

1. maximum at surface
2. maximum at centre
3. remains same throughout the conductor
4. maximum somewhere between surface and centre.

A capacitor of capacity C1 charged up to V volt and then connected to an uncharged capacitor of capacity C2. The final potential difference across each will be

1. C1VC1+C2
2. C2VC1+C2
3. (1- C2C1 )V
4. (1+ C2C1 )V

Energy per unit volume for a capacitor having area A and separation d kept at potential difference V is given by

1. 12 0 V2d2
2. 12 0 V2d2
3. 12CV2
4. Q22C

A capacitor is charged with a battery and energy stored is U. After disconnecting battery another capacitor of same capacity is connected in parallel to the first capacitor. Then energy stored in each capacitor is

1. U/2
2. U/4
3. 4U
4. 2U