Q. No.| 1. | Coulomb's law | 2. | Lenz's law |
| 3. | Biot-Savart law | 4. | Kirchoff's law |
| 1. | \(\dfrac{\mu_0i}{4r}\) |
| 2. | \(\dfrac{\mu_0i}{4r}+\dfrac{\mu_0i}{2\pi r}\) |
| 3. | \(\dfrac{\mu_0i}{4r}+\dfrac{\mu_0i}{4\pi r}\) |
| 4. | \(\left[\left(\dfrac{\mu_0i}{4r}\right)^2+\left(\dfrac{\mu_0i}{4\pi r}\right)^2\right]^{\frac12} \) |
An electron enters a chamber in which a uniform magnetic field is present as shown.
An electric field of appropriate magnitude is also applied so that the electron travels undeviated without any change in its speed through the chamber. We are ignoring gravity. Then, the direction of the electric field is:
| 1. | opposite to the direction of the magnetic field. |
| 2. | opposite to the direction of the electron's motion. |
| 3. | normal to the plane of the paper and coming out of the plane of the paper. |
| 4. | normal to the plane of the paper and into the plane of the paper. |
A long straight wire of radius \(R\) carries a uniformly distributed current \(i.\) The variation of magnetic field \(B\) from the axis of the wire is correctly presented by the graph?
| 1. |  |
2. |  |
| 3. |  |
4. |  |
1. \(1\)
2. \(2.4\)
3. \(1.4\)
4. \(2\)
1. \(M\)
2. \(M / 2 \pi\)
3. \(M / \pi\)
4. \(2M / \pi\)
A circular coil of \(30\) turns and a radius of \(8.0 ~\text{cm}\) carrying a current of \(6.0 ~\text{A}\) is suspended vertically in a uniform horizontal magnetic field of magnitude \(1.0 ~\text{T}.\) The field lines make an angle of \(60^\circ\) with the normal of the coil. What will be the magnitude of the counter-torque that must be applied to prevent the coil from turning?
1. \(7.12 ~\text{N-m}\)
2. \(3.13~\text{N-m}\)
3. \(6.50~\text{N-m}\)
4. \(4.44~\text{N-m}\)
| 1. | \(16K\) | 2. | \(8K\) |
| 3. | \(4K\) | 4. | \(K\) |
| Assertion (A): | In a uniform magnetic field, speed and energy remain the same for a moving charged particle. |
| Reason (R): | Moving charged particle experiences a magnetic force perpendicular to its direction of motion. |
| 1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
| 2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
| 3. | (A) is True but (R) is False. |
| 4. | (A) is False but (R) is True. |
| 1. | segment \(1\) | 2. | segment \(2\) |
| 3. | segment \(3\) | 4. | segment \(4\) |
© 2025 GoodEd Technologies Pvt. Ltd.