Curie temperature is the temperature above which -

1. ferromagnetic material becomes paramagnetic material 

2. paramagnetic material becomes diamagnetic material 

3. paramagnetic material becomes ferromagnetic material 

4. ferromagnetic material becomes diamagnetic material  

Domain formation is the necessary feature of : 

(1) ferromagnetism                   (2) diamagnetism

(3) paramagnetism                   (4) all of these

The magnetic susceptibility of a paramagnetic substance at \(-73^\circ\text C\) is \(0.0060,\) then its value at \(-173^\circ \text C\) will be:
1. \(0.0030\)
2. \(0.0120\)
3. \(0.0180\)
4. \( 0.0045\)

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:
            

An iron rod of length L and magnetic moment M is bent in the form of a semicircle. Now its magnetic moment will be 

1. M

2. $\frac{2\mathrm{M}}{\mathrm{\pi }}$

3. $\frac{\mathrm{M}}{\mathrm{\pi }}$

4. $\mathrm{M\pi }$

Time period of a freely suspended magnet does not depend upon 

1. length of the magnet

2. pole strength of the magnet

3. horizontal component of earth's magentic field

4. length of the suspension thread

Relative permeability of iron is 5500, then its magnetic suceptibility will be -

1. 5501

2. 5499

3. $5500\times {10}^7$

4. none of these

A current carrying coil is placed with its axis perpendicular to N-S direction. Let horizontal component of earth's magnetic field be ${\mathrm{H}}_0$ and magnetic field inside the loop be H. If a magnet is suspended inside the loop, it makes angle $\mathrm{\theta }$ with H. Then $\mathrm{\theta }$=

1. ${\tan }^{-1}\left(\frac{H_0}{H}\right)$

2. ${\tan }^{-1}\left(\frac{H}{H_{\mathit{0}}}\right)$

3. $\cos e{c}^{-1}\left(\frac{H}{H_{\mathit{0}}}\right)$

4. $co{t}^{-1}\left(\frac{H_0}{H}\right)$

A bar magnet having a magnetic moment of $2\times {10}^4 J{T}^{-1}$ is free to rotate in a horizontal plane. A horizontal magnetic field $B=6\times {10}^{-4}T$ exists in the space. The work done in taking the magnet slowly from a direction parallel to the field to a direction $60°$ from the field is 

(a) 0.6 J                            (b) 12 J

(c) 6 J                               (d) 2 J

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