If a bar magnet is kept on a horizontal plane with N-pole of bar magnet facing geographic N-pole and S-pole of bar magnet facing geographic S-pole, then the number of neutral points is:
1. | 0 | 2. | 1 |
3. | 2 | 4. | Infinite |
The correct direction of the magnetic field in the given figures is shown by:
1. | 2. | ||
3. | 4. |
A current-carrying loop is placed in a uniform magnetic field in four different orientations, I, II, III & IV. The decreasing order of potential energy is:
1. | I > III > II > IV | 2. | I > II >III > IV |
3. | I > IV > II > III | 4. | III > IV > I > II |
A bar magnet is hung by a thin cotton thread in a uniform horizontal magnetic field and is in the equilibrium state. The energy required to rotate it by is . Now the torque required to keep the magnet in this new position is:
1.
2.
3.
4.
A short bar magnet of magnetic moment is placed in a uniform magnetic field of The magnet is in stable equilibrium when the potential energy is:
1.
2. zero
3.
4.
A bar magnet of length and magnetic dipole moment is bent in the form of an arc as shown in the figure. The new magnetic dipole moment will be:
1. | 2. | ||
3. | 4. |
1. | 2. | ||
3. | 4. |
The magnetic field at a point on the axis of a small bar magnet is equal to the field at a point on the equator of the same magnet. The ratio of the distances of and from the centre of the magnet is:
1.
2.
3.
4.
Two magnets and are identical and these are arranged as shown in the figure. Their length is negligible in comparison to the separation between them. A magnetic needle is placed between the magnets at point which gets deflected through an angle under the influence of magnets. The ratio of distance and will be:
1.
2.
3.
4.
Two short magnets of equal dipole moments are fastened perpendicularly at their centres (figure). The magnitude of the magnetic field at a distance from the centre on the bisector of the right angle is:
1. | 2. | ||
3. | 4. |