Magnetism and matter practice · Medium

A magnet of $10 \mathrm{~cm}$ long and having a pole strength $2 \mathrm{~amp} \mathrm{~m}$ is deflected through $30^{\circ}$ from the magnetic meridian. The horizontal component of earth's induction is $0.32 \times 10^{-4} \mathrm{~T}$, then the value of deflecting couple is

The product of magnetic susceptibility $(\chi)$ and absolute temperature ( $T$ ) is constant for a

A material is placed in a magnetic field and it is
thrown out of it. Then the material is ______

A paramagnetic substance in the form of a cube with sides 1 cm has a magnetic dipole moment of $20 \times {10^{ - 6}}J\mathrm{/}T$ when a magnetic intensity of $60 \times {10^3}A\mathrm{/}m$ is applied. Its magnetic susceptibility is

Magnetic field strength due to a short bar magnet on its axial line at a distance x is B. Its value at the same distance on the equatorial line is

A magnet when placed at an angle of $30^\circ$ to a uniform field of strength ${10^{ - 4}}\,\,\,wb\,{m^{ - 2}}$ experiences a couple of moment $4 \times {10^{ - 5}}\,\,Nm$. What is the magnetic moment of the magnet?

Consider a short magnetic dipole of magnetic length 10 cm. Its geometric length is

Magnetic potential at any point on equatorial line of the magnetic dipole is

A magnetic dipole of moment $m$ is in a uniform magnetic field of induction $B$. If it is in stable equilibrium position in the field, the torque acting on it and potential energy are respectivley

An inductor of 10 mH shows 50 mH when operate with a core mad e of ferrite. The susceptibility of ferrite is

The example of diamagnetic, paramagnetic and
ferromagnetic materials are respectively:

Which among the following is correct regarding diamagnetic materials?

At temperature ${T_1},$ the magnetic susceptibility of a diamagnetic material is ${\chi _1}$ and at temperature ${T_2},$ it is ${\chi _2}.$ Then

A magnet of length 0.1 m and pole strength ${10^{ - 4}}$ A-m is kept in a magnetic field of 30 Wb ${\mathrm{m}^{ - 2}}$ at an angle $30^\circ .$ The couple acting on it is ……..$\times {10^{ - 4}}$ Nm.

A vertical pillar of soft iron partially embedded in earth, at south pole, is found to be magnetized by the earth's magnetic field. The polarity at the top end of the pillar will be

If a diamagnetic substance is brought near north or south pole of a bar magnet, it is

The property possessed by only ferromagnetic substance is

The relation connecting magnetic susceptibility $\chi_{\mathrm{m}}$ and relative permeability $\mu_{\mathrm{r}}$ is

A bar magnet of magnetic moment $4.0 \mathrm{~A}-\mathrm{m} 2$ is free to rotate about a vertical axis through its center. The magnet is released from rest from east-west position. Kinetic energy of the magnet in north-south position will be $(\mathrm{H}=25 \mu \mathrm{T})$

Curie temperature is the temperature above which

The radius of the coil of a tangent galvanometer which has 10 turns is 0.1 m. The current required to produce a deflection of $60^\circ \;\left( {{B_H} = 4 \times {{10}^{ - 5}}\mathrm{\;T}} \right)$ is

A short bar magnet placed with its axis at $30^{\circ}$ experiences a torque of $0.016\,\mathrm{Nm}$ in an external field of $800 \mathrm{G}$. (a) What is the magnetic moment of the magnet? (b) What is the work done by an external force in moving it from its most stable to most unstable position?

Hysteresis loss is minimized by using

The vertical component of earth’s magnetic field is zero or The earth’s magnetic field always has a vertical component except at the

At a point on the right bisector of a magnetic dipole magnetic

Magnetic materials used for making permanent magnets $(P)$ and magnets in a transformer $(T)$ have different properties, of the following, which property best matches for the type of magnet required?

Assertion: Ferro-magnetic substances become paramagnetic below Curie temp.
Reason : Domains are destroyed at high temperature

The unit of permeability of Vacuum $\left(\mu_0\right)$ is ______

Given below are two statements; one is labeled as Assertion A and the other is labeled as Reason R.

Assertion (A) : Electromagnets are made of soft iron.

Reason (R) : soft iron has high permeability and low retentivity.

In the light of above, statements, choose the most appropriate answer from the options given below.

The values of the apparent angles of dip in two planes at right angles to each other are $30^{\circ}$ and $45^{\circ}$. Calculate the true value of the angle of dip at the place.