Magnetic Properties of Matter

The electric field of a plane electromagnetic wave of amplitude $2 \mathrm{~V} \mathrm{~m}^{-1}$ varies with time and propagates along $z$-axis. The average energy density of the magnetic field (in $\mathrm{J}…

Assertion : Paramagnetic substances get poorly attracted in magnetic field. Reason : Because magnetic dipoles are aligned along external magnetic field weakly.

A paramagnetic substance of susceptibility $3 \times 10^{-4}$ is placed in a magnetising field of $4 \times 10^{-4} \mathrm{~A} \mathrm{~m}^{-1}$. Then the intensity of magnetisation in the units of $\mathrm{A}…

A bar magnet of magnetic moment $M$ and moment of inertia $I$ is freely suspended such that the magnetic axial line is in the direction of magnetic meridian. If the magnet is displaced by a very small angle $\theta$,…

A copper rod is suspended in a nonhomogeneous magnetic field region. The rod when in equilibrium will align itself

Assertion : Magnetic field is useful in producing parallel beam of charged particle. Reason : Magnetic field inhibits the motion of charged particle moving across it.

Assertion : In water, value of magnetic field decreases. Reason: Water is a diamagnetic substance.

The angle of dip at a certain place where the horizontal and vertical components of the earth's magnetic field are equal is

The angles of dip at the poles and the equator respectively are

The temperature of transition from ferromagnetic property to paramagnetic property is called

Assertion : A superconductor is a perfect diamagnetic substance.Reason : A superconductor is a perfect conductor.

Assertion : Magnetic force between two short magnets, when they are co-axial follows inverse square law of distance. Reason : The magnetic forces between two poles do not follow inverse square law of distance.