At point A on the earth's surface, the angle of dip is, $\delta =+25°$. At a point B on the earth's surface, the angle of dip is, $\delta =-25°$. We can interpret that:

The relations amongst the three elements of Earth's magnetic field, namely horizontal component H, vertical component V and dip angle$\delta$ is: ($B_E$=total magnetic field)

Which of the following property of magnetic materials is observed in all the materials?

Two small bar magnets are placed in a plane. The direction of their dipole moments and the position of magnets are as shown in the figure.

The appropriate direction of the net magnetic field at point 'P' will be indicated by which of the following arrow?

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

The magnetic susceptibility $\chi$ of a diamagnetic material depends on absolute temperature T as :

$$\begin{gathered} 1. \chi \propto T \\ 2. \chi \propto \frac{1}{T} \\ 3. \chi \propto T^0 \\ 4. \chi \propto \frac{1}{\sqrt{T}} \end{gathered}$$

The force between two magnetic poles of strength unity at a separation of 1 m is:

$$\begin{gathered} 1. 1 N \\ 2. \frac{{10}^{-7}}{4\mathrm{\pi }} \\ 3. {10}^{-7 }N \\ 4. 4\mathrm{\pi } \times {10}^{-7 }\mathrm{m} \end{gathered}$$

The magnetic lines of force inside a bar magnet are:

The material which is used to make permanent magnets has -

On a magnetic map, the lines joining the points of the same value of the horizontal component of the earth's magnetic field are called :

What is the unit of pole strength of a bar magnet?

The ratio of magnetic length and geometrical length of a bar magnet is about :

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

A substance is placed in an external magnetic field. If the direction of induced dipole moment is opposite to the direction of the applied magnetic field, then the substance may be

If B_o is magnetic flux density in vacuum produced by a magnetising force and magnetic flux density produced by the magnetisation of a material due to the same magnetising force is B_m, then the total magnetic flux density in the material is :

$$\begin{gathered} 1. B_{\circ }+ B_m \\ 2. B_{\circ }- B_m \\ 3. \frac{B_{\circ }}{B_m} \\ 4. \frac{B_m}{B_{\circ }} \end{gathered}$$

A magnet (primary) oscillates with frequency ${\mathrm{\nu }}_1$ in earth's magnetic field (B_H) alone. Now a secondary magnet is placed near the primary magnet. If B is the magnetic field of the second magnet on the primary magnet in the direction of B_H, the primary magnet oscillates with frequency ${\mathrm{\nu }}_2$, then the ratio of B/B_H is :

The angle of dip is ${\theta }_1$ on a given meridian which is at an angle $\theta$ with the magnetic meridian. If ${\theta }_2$ is the angle of dip on another meridian which is perpendicular to the first meridian, then $\mathrm{\theta }, {\mathrm{\theta }}_{1 }\mathrm{and} {\mathrm{\theta }}_2$ are related as :

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

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

The unit of intensity of the magnetising field is :

If at any place, the angle of dip is  $\theta$ and magnetic latitude is $\lambda$, then (assume that the axis of earth's magnetic moment coincides with axis of rotation of the earth)

If A is the area of the graph of the intensity of magnetisation in ferromagnetic material versus magnetising field intensity, V is the volume of the magnetic sample and n is the frequency of alternating magnetic field, then the rate of hysteresis loss in the substance is 

A magnet is oscillating with the time period 'T' in a vertical plane. If the angle of dip at that place is 60$°$ and the magnet is restricted to oscillate in the horizontal plane, then the time period of oscillations will be :

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 :

The true value of the angle of dip at a place is $\theta$. If the plane of the dip circle is at 30$°$ with the magnetic meridian, the angle of dip is $\theta$'. Then one concludes that :

A diamagnetic substance is kept in a uniform external magnetic field B. If the net magnetic field inside the substance is B', then

The lines joining the places of zero declination are called :

A magnetic needle makes n oscillations per minute in a horizontal plane where the angle of dip is 45$°$. If the needle is made to oscillate in a vertical plane coinciding with the magnetic meridian, then the number of oscillations per minute will become/remains

Two similar nature magnetic poles of strength 16 A-m and 64 A-m are placed at a distance of 120 cm in air. At which point on the line joining the two poles, the force on another unit north pole will be zero?

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: