Which of the following is not dimensionless?
(where symbols stand for their usual meanings in magnetism)

1. $\frac{I}{H}$

2. $\frac{B}{{\mu }_{0}H}$

3. ${\mu }_r$

4. $\frac{{\mu }_{r}B}{H}$

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:

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

Due to a small magnet, the intensity at a distance \(x\) in the end-on position is \(9~\text{gauss}\). What will be the intensity at a distance \(\frac{x}{2}\) on equatorial position?
1. \(9~\text{gauss}\)
2. \(4~\text{gauss}\)
3. \(36~\text{gauss}\)
4. \(4.5~\text{gauss}\)

The possible value of magnetic susceptibility of a diamagnetic material can be:

1. -2.45

2. 0.75

3. -0.5

4. 1.67

The bar magnet \(A\) of magnetic moment \(M_A\) is found to oscillate at a frequency twice that of magnet \(B\) of magnetic moment \(M_B\) and the same moment of inertia when placed in a vibration magnetometer. We may say that:
1. \(M_B=8M_A\)
2. \(M_A= 4M_B\)
3. \(M_A=8M_B\)
4. \(M_A=2M_B\)

When a magnetic material is subjected to a very small magnetising force \(H,\) the intensity of magnetisation is proportional to:

The magnetization of a piece of iron or steel:

A Gaussian surface is drawn enclosing the N-pole of a bar magnet. The net magnetic flux through the Gaussian surface will be:
(pole strength of N-pole is treated as positive and S-pole as negative)