The earth's magnetic field at a certain place has a horizontal component 0.3 Gauss and the total strength 0.5 Gauss. The angle of dip is:

1. ${\tan }^{-1}\left(\frac{3}{4}\right)$                     

2. ${\sin }^{-1}\left(\frac{3}{4}\right)$

3. ${\tan }^{-1}\left(\frac{4}{3}\right)$                     

4. ${\sin }^{-1}\left(\frac{3}{5}\right)$

If H is the horizontal component of the earth's magnetic field and 'V' is the vertical component of the earth's magnetic field, then at the magnetic equator:

1. V and H are equal.

2. values of V and H are zero.

3. value of H is zero only.

4. value of V is zero only.

An electric cable is carrying current from north to south. The position of the null point from the cable is:

1. Vertically upward

2. Vertically downward

3. Eastward

4. Nowhere

Which of the following graphs represents the correct variation of the intensity of magnetisation (I) with the intensity of the magnetising field (H) in a ferromagnetic substance?

1.		2.
3.		4.

The magnetic susceptibility χ of a ferromagnetic material varies with temperature, as:

1.		2.
3.		4.

At a place, the angle of dip is 30$°$. If the horizontal component of the earth's magnetic field is B, the total intensity is:

1. $\frac{\sqrt{3}B}{2}$

2. $\frac{2B}{\sqrt{3}}$

3. 2B

4. B$\sqrt{3}$

A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It will:

1. stay in the east-west direction only.

2. stay in any position.

3. become rigid showing no movement.

4. stay in the north-south direction only.

If a bar magnet is kept on a horizontal plane with N-pole of bar magnet facing geographic N-pole and S-pole of bar magnet facing geographic S-pole, then the number of neutral points is:

A material when heated suddenly changes its magnetic property at a particular temperature and above this temperature, its susceptibility is found to be inversely proportional to the absolute temperature. The material may be:

1. Ferromagnetic

2. Diamagnetic

3. Paramagnetic

4. Ferromagnetic or Paramagnetic

As we go from the magnetic equator towards the geographic south pole, the angle of the dip will become: