The electrostatic force between the metal plates of an isolated parallel plate capacitor C having a charge Q and area A is:
1. | independent of the distance between the plates. |
2. | linearly proportional to the distance between the plates. |
3. | proportional to the square root of the distance between the plates. |
4. | inversely proportional to the distance between the plates. |
The diagrams below show regions of equipotentials.
A positive charge is moved from A to B in each diagram. Then:
1. | the maximum work is required to move q in figure(iii). |
2. | in all four cases, the work done is the same. |
3. | the minimum work is required to move q in the figure(i). |
4. | the maximum work is required to move q in figure(ii). |
A capacitor is charged by a battery. The battery is removed and another identical uncharged capacitor is connected in parallel. The total electrostatic energy of resulting system:-
1. Decreases by a factor of 2
2. Remains the same
3. Increases by a factor of 2
4. Increases by a factor of 4
An electric dipole is place at an angle of \(30^{\circ}\) with an electric field intensity \(2\times10^{5}~\text{N/C}\). It experiences a torque equal to \(4~\text{Nm}\). The charge on the dipole, if the dipole length is \(2~\text{cm}\), is:
1. | \(8~\text{mC}\) | 2. | \(2~\text{mC}\) |
3. | \(5~\text{mC}\) | 4. | \(7~\mu\text{C}\) |
A parallel-plate capacitor of area A, plate separation d, and capacitance C is filled with four dielectric materials having dielectric constants and as shown in the figure below. If a single dielectric material is to be used to have the same capacitance C in this capacitor, then its dielectric constant k is given by
(a)
(b)
(c)
(d)
A capacitor of \(2\) µF is charged as shown in the figure. When the switch \(\mathrm{S}\) is turned to position \(2,\), the percentage of its stored energy dissipated is: