Among the following properties describing diamagnetism identify  the property that is wrongly stated

1. Diamagnetic material do not have permanent magnetic moment

2. Diamagnetism is explained in terms of electromagnetic induction

3. Diamagnetic materials have a small positive susceptibility

4. The magnetic moment of individual electrons neutralize each other

If a magnet is suspended at an angle 30^o to the magnetic meridian, it makes an angle of 45^o with the horizontal. The real dip is

(a)${\tan }^{-1}\left(\frac{\sqrt{3}}{2}\right)$

(b)${\tan }^{-1}\left(\sqrt{3}\right)$

(c)${\tan }^{-1}\left(\sqrt{\frac{3}{2}}\right)$

(d)${\tan }^{-1}\left(\frac{2}{\sqrt{3}}\right)$

The true value of angle of dip at a place is 60^o, the apparent dip in a plane inclined at an angle of 30^o with magnetic meridian is

(1)${\tan }^{-1}\left(\frac{1}{2}\right)$

(2)${\tan }^{-1}\left(2\right)$

(3)${\tan }^{-1}\left(\frac{2}{3}\right)$

(4)None of these

Two magnets A and B are identical and these are arranged as shown in the figure. Their length is negligible in comparison to the separation between them. A magnetic needle is placed between the magnets at point P which gets deflected through an angle $\theta$ under the influence of magnets. The ratio of distance d₁ and d₂ will be:

1. $(2 \tan \theta {)}^{1/3}$

2. $(2 \tan \theta {)}^{-1/3}$

3. $(2 cot \theta {)}^{1/3}$

4. $(2 cot \theta {)}^{-1/3}$

Two short magnets of equal dipole moments M are fastened perpendicularly at their centres (figure). The magnitude of the magnetic field at a distance 'd' from the centre on the bisector of the right angle is:

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

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

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

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

The variation of magnetic susceptibility $\left(\chi \right)$ with temperature for a diamagnetic substance is best represented by:

1.		2.
3.		4.

The variation of magnetic susceptibility $\left(\chi \right)$ with absolute temperature T for a ferromagnetic material is

The relative permeability $\left({\mu }_r\right)$ of a ferromagnetic substance varies with temperature (T) according to the curve

(1) A                              

(2) B

(3) C                              

(4) D

The variation of the intensity of magnetisation (I) with respect to the magnetising field (H) in a diamagnetic substance is described by the graph:

If ${\theta }_1 and {\theta }_2$ be the apparent angles of dip observed in two vertical planes at right angles to each other, then the true angle of dip $\theta$ is given by 

(a) $co{t}^2\theta =co{t}^2{\theta }_1+co{t}^2{\theta }_2$

(b) ${\tan }^2\theta ={\tan }^2{\theta }_1-{\tan }^2{\theta }_2$

(c) $co{t}^2\theta =co{t}^2{\theta }_1-{\tan }^2{\theta }_2$

(d) ${\tan }^2\theta ={\tan }^2{\theta }_1-{\tan }^2{\theta }_2$