### MCQs of Magnetism and Matter

Showing 1 to 10 out of 145 Questions
1.
A magnet of magnetic dipole moment 5.0 A m2 is lying in a uniform magnetic field of 7 × 10-4 T such that its dipole moment vector makes an angle of 30° with the field. The work done in increasing this angle from 30° to 45° is about _____ J.
 (a) 5.56 × 10-4 (b) 24.74 × 10-4 (c) 30.3 × 10-4 (d) 5.50 × 10-3
2.
A bar magnet is oscillating in Earth's magnetic field with periodic time T. If a similar magnet with the same mass and volume has magnetic dipole moment, which is 4 times that of this magnet, then its periodic time will be _____ .
 (a) $\frac{\mathrm{T}}{2}$ (b) 2T (c) T (d) 4T
3.
A circular loop carrying current I is replaced by a bar magnet of equivalent magnetic dipole moment. The point on the loop is lying _____.
 (a) on equatorial plane of magnet (b) on axis of the magnet (c) A and B both (d) except equatorial plane or axis of bar magnet
4.
When a current carrying loop is replaced by an equivalent magnetic dipole
 (a) the distance l between the poles is fixed. (b) the pole strength p of each pole is fixed. (c) the dipole moment is reversed. (d) the product pl is fixed.
5.
Let r be a distance of the point on the axis of a bar magnet from its centre. The magnetic field at r always proportional to
 (a) $\frac{1}{{\mathrm{r}}^{2}}$ (b) $\frac{1}{{\mathrm{r}}^{3}}$ (c) $\frac{1}{\mathrm{r}}$ (d)
6.
Magnetic meridian is a plane _____.
 (a) perpendicular to magnetic axis of Earth. (b) perpendicular to geographic axis of Earth. (c) passing through the magnetic axis of Earth. (d) passing through the geographic axis.
7.
At geomagnetic pole, a magnetic needle allowed to rotate in horizontal plane will
 (a) stay in north-south direction only (b) stay in any position (c) stay in east-west direction only (d) become rigid showing no movement
8.
The horizontal and vertical components of magnetic field of Earth are same at some place on the surface of Earth. The magnetic dip angle at this place will be _____ .
 (a) 30° (b) 45° (c) 0° (d) 90°
9.
Inside a bar magnet, the magnetic field lines
 (a) are not present (b) are parallel to the cross-sectional area of the magnet (c) are in the direction from N-pole to S-pole (d) are in the direction from S-pole to N-pole
10.
In non-uniform magnetic field, a diamagnetic substance experiences a resultant force
 (a) from the region of strong magnetic field to the region of weak magnetic field. (b) perpendicular to the magnetic field. (c) from the region of weak magnetic field to the region of strong magnetic field. (d) which is zero
Showing 1 to 10 out of 145 Questions