Two equal positive charges are kept at points \(A\) and \(B\). The electric potential at the points between \(A\) and \(B\) (excluding these points) is studied while moving from \(A\) to \(B\). The potential:
1. | continuously increases. |
2. | continuously decreases. |
3. | increases then decreases. |
4. | decreases then increases. |
A point charge \(q\) is rotated along a circle in the electric field generated by another point charge \(Q\). The work done by the electric field on the rotating charge in one complete revolution is:
1. | zero. |
2. | positive. |
3. | negative. |
4. | zero if the charge \(Q\) is at the centre and non-zero otherwise. |
The energy density in the electric field created by a point charge falls off with the distance from the point charge as
1. \(1 \over r\)
2. \(1 \over r^2\)
3. \(1 \over r^3\)
4. \(1 \over r^4\)