Select the incorrect statement regarding magnetic material.

1.	The magnetic dipole moment of each atom of para and ferromagnetic substance is zero and that of diamagnetic material is non-zero in the absence of external magnetizing force
2.	When the diamagnetic substance is brought near the north or south pole of a bar magnet, it is repelled
3.	Magnetic susceptibility of diamagnetic substances is temperature independent and that of para and ferromagnetic substances is temperature-dependent
4.	All of these

When cooled below \(4.2\) K, mercury becomes a superconductor, which means it has no electrical resistance. When a current is passed through mercury under these conditions, which one of the following effects will be present?
(a) thermal
(b) chemical
(c) magnetic

A bar magnet has coercivity $4\times {10}^3$ $A{m}^{-1}$. It is desired to demagnetize it by inserting it inside a solenoid 12 cm long and having 60 turns. The current that should be sent through the solenoid is:

1. 2 A

2. 4 A

3. 6 A

4. 8 A

A uniform magnetic field, parallel to the plane of the paper existed in space initially directed from left to right. When a bar of soft iron is placed in the field parallel to it, the lines of force passing through it will be represented by:

1.		2.
3.		4.

A superconductor exhibits perfect:
1. Ferrimagnetism
2. Ferromagnetism
3. Paramagnetism             
4. Diamagnetism

Two short magnets of equal dipole moments M are fastened perpendicularly at their centres (figure). The magnitude of the magnetic field at a distance 'd' from the centre on the bisector of the right angle is:

1. $\frac{{\mu }_0}{4\mathrm{\pi }}$ $\frac{M}{d^3}$ $$

2. $\frac{{\mu }_0}{4\mathrm{\pi }}$ $\frac{M\sqrt{2}}{d^3}$

3. $\frac{{\mu }_0}{4\mathrm{\pi }}$ $\frac{2\sqrt{2}M}{d^3}$

4. $\frac{{\mu }_0}{4\mathrm{\pi }}$ $\frac{2M}{d^3}$

The variation of magnetic susceptibility $\left(\chi \right)$ with temperature for a diamagnetic substance is best represented by:

1.		2.
3.		4.

The variation of the intensity of magnetisation (I) with respect to the magnetising field (H) in a diamagnetic substance is described by the graph:

If a diamagnetic substance is brought near the north or the south pole of a bar magnet, it is:

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