If a diamagnetic substance is brought near the north or the south pole of a bar magnet, it is:
1. | repelled by both the poles |
2. | repelled by the north pole and attracted by the south pole |
3. | attracted by the north pole and repelled by the south pole |
4. | attracted by both the poles |
The magnetic dipoles in a diamagnetic material are represented, for three situations. The three situations differ in magnitude if a magnetic field is applied to the material. In which situation the magnetization of the material is the greatest:
1. A
2. B
3. C
4. equal in A, B, and C
Two bar magnets are held together tightly in a vibration magnetometer. When their like poles are together, they make 20 oscillations per minute and when their unlike poles are together, they make 8 oscillations per minute. The ratio of the magnetic dipole moments of two bar magnets is:
1. 29:21
2. 6:15
3. 1:6
4. 25:4
The magnetic susceptibility of a diamagnetic material depends on absolute temperature T as:
The magnetic lines of force inside a bar magnet are:
1. | from south to the north pole. |
2. | from north to the south pole. |
3. | not present. |
4. | intersecting each other. |
The material which is used to make permanent magnet has:
1. | High retentivity, low coercivity |
2. | Low retentivity, low coercivity |
3. | Low retentivity, high coercivity |
4. | High retentivity, high coercivity |
Which of the following is not dimensionless?
(where symbols stand for their usual meanings in magnetism)
1.
2.
3.
4.
The magnetic moment of a short dipole is \(100\) A-m2. The magnetic induction in vacuum at \(1\) m from the dipole on the axis of the dipole is:
1. \(2\times10^{-5}~\text{T}\)
2. \(10^{-5}~\text{T}\)
3. \(2~\mu\text{T}\)
4. \(1~\mu\text{T}\)
The magnetic moment of a magnet \((10 ~cm\times 4~cm\times1~cm)\) is \(4 ~Am^2\). Its intensity of magnetisation is:
1. 103 A/m
2. 102 A/m
3. 105 A/m
4. 104 A/m
S.I. unit of intensity of magnetization is:
1. | Ampere-metre | 2. | Ampere-metre2 |
3. | Ampere/metre | 4. | Ampere/metre2 |