Which of the following is the correct representation of magnetic field lines?

 

1. (g), (c)

2. (d), (f)

3. (a), (b)

4. (c), (e)

If the magnetic dipole moment of an atom of diamagnetic material, paramagnetic material and ferromagnetic material are denoted by µ_d, µ_p, and µ_f respectively, then:

1. µ_p = 0 and µ_f ≠ 0

2. µ_d ≠ 0 and µ_p = 0

3. µ_d ≠ 0 and µ_f ≠ 0

4. µ_d = 0 and µ_p ≠ 0

Figure shows two small identical magnetic dipoles a and b of magnetic moments M each, placed at a separation 2d, with their axes perpendicular to each other. The magnetic field at the point P midway between the dipoles is:

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

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

3. Zero

4. $\frac{\sqrt{5}{\mathrm{\mu }}_0\mathrm{M}}{4{\mathrm{\pi d}}^3}$

Choose the correct statement regarding magnetism.

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)

The magnetization of a piece of iron or steel:

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 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

The material which is used to make permanent magnet has:

There are four light-weight-rod samples; A, B, C, D separately suspended by threads. A bar magnet is slowly brought near each sample and the following observations are noted:

Which one of the following is true?