A parallel plate air capacitor is charged to potential difference V. After disconnecting the battery, the distance between the plates of the capacitor is increased using an insulating handle. As a result the potential difference between the plates:
1. decreases.
2. increases.
3. becomes zero.
4. does not change.
A short electric dipole has a dipole moment of \(16 \times 10^{-9} ~\text{C-}\text{m}\). The electric potential due to the dipole at a point at a distance of \(0.6~\text{m}\) from the centre of the dipole situated on a line making an angle of \(60^{\circ}\) with the dipole axis is: \(\left( \frac{1}{4\pi \varepsilon_0}= 9\times 10^{9}~\text{N-m}^2/\text{C}^2\right)\)
1. \(200~\text{V}\)
2. \(400~\text{V}\)
3. zero
4. \(50~\text{V}\)
The increasing order of the electrostatic potential energies for the given system of charges is given by:
1. | a = d < b < c | 2. | b = d < c < a |
3. | b = c < a < d | 4. | c < a < b < d |
Some equipotential surfaces are shown in figure. The electric field at points A, B and C are respectively:
1. | \(1 \mathrm{~V} / \mathrm{cm}, \frac{1}{2} \mathrm{~V} / \mathrm{cm}, 2 \mathrm{~V} / \mathrm{cm} \text { (all along +ve X-axis) }\) |
2. | \(1 \mathrm{~V} / \mathrm{cm}, \frac{1}{2} \mathrm{~V} / \mathrm{cm}, 2 \mathrm{~V} / \mathrm{cm} \text { (all along -ve X-axis) }\) |
3. | \(\frac{1}{2} \mathrm{~V} / \mathrm{cm}, 1 \mathrm{~V} / \mathrm{cm}, 2 \mathrm{~V} / \mathrm{cm} \text { (all along +ve X-axis) }\) |
4. | \(\frac{1}{2} \mathrm{~V} / \mathrm{cm}, 1 \mathrm{~V} / \mathrm{cm}, 2 \mathrm{~V} / \mathrm{cm} \text { (all along -ve X-axis) }\) |
What is the area of the plates of a \(2~\text{F}\) parallel plate capacitor, given that the separation between the plates is \(0.5~\text{cm}\)?
1. \(1100~\text{km}^2\)
2. \(1130~\text{km}^2\)
3. \(1110~\text{km}^2\)
4. \(1105~\text{km}^2\)
If \(50~\text{J}\) of work must be done to move an electric charge of \(2~\text{C}\) from a point where the potential is \(-10\) volt to another point where the potential is \(\mathrm{V}\) volt, then the value of \(\mathrm{V}\) is:
1. \(5\) volt
2. \(-15\) volt
3. \(+15\) volt
4. \(+10\) volt
Which of the following statements is correct regarding electrostatics of conductors?
1. | The interior of the conductor with no cavity can have no excess charge in the static situation. |
2. | Electrostatic potential is constant throughout the volume of the conductor. |
3. | Electrostatic potential has the same value inside as that on its surface. |
4. | All of these. |
Two capacitors of capacity and are charged to the same potential difference of 6 V. Now they are connected with opposite polarity as shown. After closing switches , their final potential difference becomes:
1. | \(\text{Zero} \) | 2. | \(\frac{4}{3} \mathrm{~V} \) |
3. | \(3 \mathrm{~V} \) | 4. | \(\frac{6}{5} \mathrm{~V}\) |
The equivalent capacitance across \(A\) and \(B\) in the given figure is:
1. \( \frac{3}{2}C\)
2. \(C\)
3. \( \frac{2}{3}C\)
4. \( \frac{5}{3}C\)
Two concentric metallic spherical shells A and B of radii a and b respectively (b>a) are arranged such that outer shell is earthed and inner shell is charged to Q. Charge on the outer surface of outer shell will be:
1.
2.
3. -Q
4. zero