The magnetic susceptibility of a substance is -0.0002 at room temperature. If this substance is kept in a uniform external magnetic field B, the net field inside the substance becomes B', then :

1. B'$>$B

2. B'$<$B

3. B' = B

4. B' = 0

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:

The magnetic moment of a magnet \((10 ~\text{cm}\times 4~\text{cm}\times1~\text{cm})\) is \(4 ~\text{Am}^2\). Its intensity of magnetisation is:
1. \(10^{3}\) A/m
2. \(10^{2}\) A/m
3. \(10^{5}\) A/m
4. \(10^{4}\) A/m

S.I. unit of intensity of magnetization is:

A ferromagnetic material is placed in an external magnetic field. The magnetic domains:

If a magnetic dipole of dipole moment $\mu$ is rotated through an angle $\theta$ with respect to the direction of the magnetic field B, then work done is :

1. $\mu$Bsin$\theta$

2. $\mu$B(1-sin$\theta$)

3. $\mu$Bcos$\theta$

4. $\mu$B(1-cos$\theta$)

Magnetic permeability is maximum for

1. Diamagnetic substance

2. Paramagnetic substance

3. Ferromagnetic substance

4. Same for all three substances

The magnetic moment of a bar magnet shown in figure(i) is M.

If a hole is drilled through the magnet as shown in figure(ii), then the new magnetic moment of the magnet will be :

1. Equal to M

2. Less than M

3. More than M

4. Zero

When a substance is kept in a magnetic field, it gets repelled. Which of the following represents its susceptibility?

1. -0.0004

2. 0.0004

3. 1.000

4. -1.000

Magnetic susceptibility of a substance at \(27^{\circ}~\mathrm{C}\) is \(-0.00025\). Its magnetic susceptibility at \(127^{\circ}~\mathrm{C}\) is:
1. \(-0.000125\)
2. \(-0.0005\)
3. \(-0.00025\)
4. \(-0.00001\)