A \(12\) pF capacitor is connected to a \(50\) V battery. How much electrostatic energy is stored in the capacitor?
1. | \(3.1\times10^{-8}\) J | 2. | \(2.9\times10^{-8}\) J |
3. | \(3.3\times10^{-8}\) J | 4. | \(1.5\times10^{-8}\) J |
A \(600\) pF capacitor is charged by a \(200\) V supply. It is then disconnected from the supply and is connected to another uncharged \(600\) pF capacitor. How much electrostatic energy is lost in the process?
1. \( 5 \times 10^{-6} \) J
2. \( 6 \times 10^{-5} \) J
3. \( 6 \times 10^{-6} \) J
4. \( 5 \times 10^{-5}\) J
A charge of 8 mC is located at the origin. The work done in taking a small charge of from a point P (0, 0, 3 cm) to a point Q (0, 4 cm, 0), via a point R (0, 6 cm, 9 cm) is:
1. 3.27 J
2. 1.27 J
3. 0.27 J
4. 2.70 J
A cube of side b has a charge q at each of its vertices. The potential due to this charge array at the center of the cube is:
1. \(\frac{4q}{\sqrt3\pi\varepsilon_0b}\)
2. \(\frac{8q}{\sqrt3\pi\varepsilon_0b}\)
3. \(\frac{2q}{\sqrt3\pi\varepsilon_0b}\)
4. \(0\)
Two tiny spheres carrying charges of \(1.5\) µC and \(2.5\) µC are located \(30\) cm apart. What is the potential at a point \(10\) cm from the midpoint in a plane normal to the line and passing through the mid-point?
1. \(1.5\times 10^{5}\) V
2. \(1.0\times 10^{5}\) V
3. \(2.4\times 10^{5}\) V
4. \(2.0\times 10^{5}\) V
1. | \(-23.1\) eV | 2. | \(27.0\) eV |
3. | \(-27.2\) eV | 4. | \(23.7\) eV |
Two charged conducting spheres of radii a and b are connected to each other by a wire. The ratio of electric fields at the surfaces of the two spheres is:
1. | \(\dfrac{a}{b}\) | 2. | \(1\) |
3. | \(\dfrac{2a}{b}\) | 4. | \(\dfrac{b}{a}\) |
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. \(1105~\text{km}^2\)
The equivalent capacitance of the circuit is:
1. \(200\) pF
2. \(\frac{200}{3}\) pF
3. \(200\) \(\mu\)F
4. \(150\) pF
The plates of a parallel plate capacitor have an area of \(90\) cm2 each and are separated by \(2.5\) mm. The capacitor is charged by connecting it to a \(400\) V supply. How much electrostatic energy is stored by the capacitor?
1. \(1.7\times10^{-6}\) J
2. \(2.12\times10^{-6}\) J
3. \(2.55\times10^{-6}\) J
4. \(1.66\times10^{-6}\) J