Idea behind a PPC

Q. A parallel plate capacitor filled with air has a capacitance of $C$. The distance of separation between the plates is $d$ and the potential difference of $V$ is applied between the plates. Force of attraction between the plates of the parallel plate capacitor is

1. $\frac{C^2{V}^2}{2d^2}$
2. $\frac{C^2{V}^2}{2d}$
3. $\frac{C{V}^2}{2d}$
4. $\frac{C^{2}V}{d}$

Q. A capacitor of capacitance $4\mu \text{F}$ can withstand a maximum voltage of $10\text{V}$. Another capacitor of capacitance $3\mu \text{F}$ can withstand a maximum voltage of $8\text{V}$. If the capacitors are connected in parallel, the combination can withstand a maximum voltage of

1. $5\text{V}$
2. $8\text{V}$
3. $4\text{V}$
4. $10\text{V}$

Q. Capacitance C depends only on the geometrical configuration (shape, size, separation) of the system of two conductors and on the nature of the dielectric separating the two conductors.

1. False
2. True

Q. In a parallel plate capacitor, when the total charge is zero, all charges reside on the inner faces facing each other and no charges comes on the outer face.

1. False
2. True

Q. A capacitor having $C=10\mu F$; Potential across plates, V = 10V; Distance between plates 10mm; And area of plates $10c{m}^2$, has air between the plates. What is the force on one of the plates.

1. $4.65\times {10}^{5}N$
2. $5.65\times {10}^{5}N$
3. $6.65\times {10}^{5}N$
4. None of these

Q. A parallel plate capacitor filled with air has a capacitance of $C$. The distance of separation between the plates is $d$ and the potential difference of $V$ is applied between the plates. Force of attraction between the plates of the parallel plate capacitor is

1. $\frac{C^2{V}^2}{2d^2}$
2. $\frac{C^2{V}^2}{2d}$
3. $\frac{C{V}^2}{2d}$
4. $\frac{C^{2}V}{d}$

Q. A capacitor having $C=10\mu F$; Potential across plates, V = 10V; Distance between plates 10mm; And area of plates $10c{m}^2$, has air between the plates. What is the force on one of the plates.

1. $4.65\times {10}^{5}N$
2. $5.65\times {10}^{5}N$
3. $6.65\times {10}^{5}N$
4. None of these

Q. Figure shows two conducting thin concentric shells of radii $r$ and $3r$. The outer shell carries a charge $q$ and the inner shell is neutral. The charge that will flow from inner shell to earth after the switch $S$ is closed is

1. $+\frac{q}{2}$
2. $-\frac{q}{3}$
3. $-\frac{q}{2}$
4. $+\frac{q}{3}$