The effective capacity of the network between terminals \(\mathrm{A}\) and \(\mathrm{B}\) is:
1. \(6~\mu\text{F}~\)
2. \(20~\mu\text{F} ~\)
3. \(3~\mu\text{F}~\)
4. \(10~\mu\text{F}\)
Eight equally charged tiny drops are combined to form a big drop. If the potential on each drop is 10 V, then the potential of the big drop will be:
1. | 40 V | 2. | 10 V |
3. | 30 V | 4. | 20 V |
A bullet of mass 2 g is having a charge of 2 µC. Through what potential difference must it be accelerated, starting from rest, to acquire a speed of 10 m/s?
1. 50 kV
2. 5 V
3. 50 V
4. 5 kV
An electric dipole has the magnitude of its charges as q and its dipole moment is p. It is placed in a uniform electric field E. If its dipole moment is along the direction of the field, the force on it and its potential energy are respectively:
1. | q.E and p.E |
2. | zero and minimum |
3. | q.E and maximum |
4. | 2q.E and minimum |
The energy and capacity of a charged parallel plate capacitor are \(E\) and \(C\) respectively. If a dielectric slab of \(E_r=6\) is inserted in it, then the energy and capacity become:
(Assuming the charge on plates remains constant)
1. | \(6 \mathrm E,~6 \mathrm C\) | 2. | \( \mathrm E,~ \mathrm C\) |
3. | \({E \over 6},~6 \mathrm C\) | 4. | \( \mathrm E,~6 \mathrm C\) |
A capacitor of capacity C1 is charged up to V volt and then connected to an uncharged capacitor C2. Then final P.D. across each will be:
1.
2.
3.
4.
Three capacitors each of capacity \(4\) µF are to be connected in such a way that the effective capacitance is \(6\) µF. This can be done by:
1. | connecting all of them in a series. |
2. | connecting them in parallel. |
3. | connecting two in series and one in parallel. |
4. | connecting two in parallel and one in series. |
Two parallel metal plates having charges +Q and –Q, face each other at a certain distance between them. If the plates are now dipped in the kerosene oil tank, the electric field between the plates will:
1. | increase. | 2. | decrease. |
3. | remain the same. | 4. | become zero. |
The electric potential V at any point (x, y, z), all in meters in space is given by V = volt. The electric field at the point (1, 0, 2) in volt/meter, is:
1. | 8 along the negative X-axis |
2. | 8 along the positive X-axis |
3. | 16 along the negative X-axis |
4. | 16 along the positive X-axis |
Three charges, each \(+q\), are placed at the corners of an equilateral triangle \(ABC\) of sides \(BC\), \(AC\), and \(AB\). \(D\) and \(E\) are the mid-points of \(BC\) and \(CA\). The work done in taking a charge \(Q\) from \(D\) to \(E\) is:
1. | \(\frac{3qQ}{4\pi \varepsilon_0 a}\) | 2. | \(\frac{3qQ}{8\pi \varepsilon_0 a}\) |
3. | \(\frac{qQ}{4\pi \varepsilon_0 a}\) | 4. | \(\text{zero}\) |