Magnetism and M...

The torque and magnetic potential energy of a magnetic dipole in most stable position in a uniform magnetic field($$\bar{B}$$) having magnetic moment ($$\bar{m}$$) will be.

If a magnetic material is having magnetic susceptibility $$(\chi)=-1$$, then the relative magnetic permeability $$(\mu_r)$$ and type of magnetic material is?

Assertion : Substances which at room temperature retain their ferromagnetic property for a long period of time are called permanent magnets.
Reason : Permanent magnet can be made by placing a ferromagnetic rod in a solenoid and passing current through it.

Assertion : At high temperature, a ferromagnet becomes a paramagnet.
Reason : The ferromagnetic property depends on temperature.

A ball of superconducting material is dipped in liquid nitrogen and placed near a bar magnet. In which direction will it move?

Two magnets of movement M and 2M are tied at an angle of $$60^0$$ to each other. What is the resultant magnetic moment of the combination?

Short Answer Type Question.
Which magnetic property is present in all substances?

The magnetic field of earth at the equator is approximately $$4\times 10^{-5}\ T$$. The radius of earth is $$6.4\times 10^{6}\ m$$. Then the dipole moment of the earth will be near the order of

The coercivity of a small magnet where the ferromagnet gets demagnetized is $$3\times 10^{3}\ Am^{-1}$$. The current required to be passed in a solenoid of length $$10\ cm$$ and number of turns $$100$$, so that the magnet gets demagnetized when inside the solenoid, is:

Core of electromagnets are made of ferromagnetic materials which have.