Q. No.What is the relation between voltage sensitivity \((\sigma_v)\) and current sensitivity \((\sigma_i)\) of a moving coil galvanometer? (Resistance of Galvanometer = \(G\))
1. \(\frac{\sigma_{i}}{G} = \sigma_{v}\)
2. \(\frac{\sigma_{v}}{G} =\sigma_{i}\)
3. \(\frac{G}{\sigma_{v}} =\sigma_{i}\)
4. \(\frac{G}{\sigma_{i}} =\sigma_{v}\)
| 1. | putting in series resistance of \(240 ~\Omega \text {. }\) |
| 2. | putting in parallel resistance of \(240 ~\Omega \text {. }\) |
| 3. | putting in series resistance of \(15~ \Omega \text {. }\) |
| 4. | putting in parallel resistance of \(15~ \Omega \text {. }\) |
| 1. | \(nB\) | 2. | \(n^2B\) |
| 3. | \(2nB\) | 4. | \(2n^2B\) |
| 1. | infinite | 2. | zero |
| 3. | \( \frac{\mu_0 2 i}{4 \pi} ~\text{T} \) | 4. | \( \frac{\mu_0 i}{2 r} ~\text{T} \) |
(\(R\) = radius of the coil)
| 1. | \(R \over 3\) | 2. | \(\sqrt{3}R\) |
| 3. | \(R \over \sqrt3\) | 4. | \(R \over 2\) |
1. \(1\) cm
2. \(\sqrt{2}\) cm
3. \(2\) cm
4. \(4\) cm
A wire of length \(l\) carrying current \(i\) is folded to form a circular coil of \(N\) turns. What should be the value of \(N\) to have the maximum value of the magnetic moment in the coil?
1. \(1\)
2. \(4\)
3. \(9\)
4. \(10\)
If charge \(-Q\) is moving vertically upwards, then what will be the force on the charged particle if it enters a magnetic field that is pointed towards the south?
1. North
2. South
3. East
4. West
What happens when the number of turns in a galvanometer is doubled?
| 1. | The voltage sensitivity becomes double. |
| 2. | The current sensitivity becomes double. |
| 3. | the voltage sensitivity becomes half. |
| 4. | The current sensitivity remains the same. |
The two parts of the loop are circles of radii \(2a\) and \(a,\) respectively, and carry the same current \(i\) as shown in the given figure. What is the magnitude of the dipole moment of the current loop?
1. \(5 \pi a^{2}\hat i\)
2. \(4 \pi a^{2}\hat i\)
3. \(3 \pi a^{2}\hat i\)
4. zero
© 2026 GoodEd Technologies Pvt. Ltd.