MCQs of Magnetism and Matter

Magnetism and Matter MCQs

MCQs of Magnetism and Matter

Showing 31 to 40 out of 145 Questions

31.

A bar magnet is oscillating in the earth's magnetic field with a time period T. If its mass is quadrupled, then its time period will be _____ .

(a) $\frac{T}{2}$

(b) T

(c) 2T

(d) 4T

32.

The unit of magnetic permeability is _____ .

(a)	Henry
(b)	Henry/m
(c)	Henry m
(d)	weber/m²

33.

The correct relation between B, H and M is _____ .

(a) B = μ₀ (M + H)

(b) B = μ₀ (M - H)

(c) $B = \frac{μ_{0} M}{H}$

(d) B = μ₀M × μ₀H

34.

If the magnetic flux is expressed in Weber, the unit of magnetic induction is _____ .

(a)	$\frac{Wb}{m}$
(b)	$Wb \times m$
(c)	$Wb \times m^{2}$
(d)	$\frac{Wb}{m^{2}}$

35.

A bar magnet of magnetic moment

\vec{m}

, is placed in a magnetic field of induction

\vec{B}

. The torque exerted on it is _____ .

(a)	$\vec{m} \times \vec{B}$
(b)	$\vec{B} . \vec{m}$
(c)	$\vec{m} . \vec{B}$
(d)	$- \vec{m} . \vec{B}$

36.

For _____, domain structure is a necessary property.

(a)	ferromagnetic substances
(b)	diamagnetic subsatance
(c)	paramagnetic substances
(d)	all dia, para, and ferro magnetic substances

37.

At a given place on the Earth, the angle between the magnetic meridian and the geographic meridian is called _____ .

(a)	magnetic latitude
(b)	magnetic dip
(c)	magnetic longitude
(d)	magnetic declination

38.

There are 2.0 × 10²⁴ molecular dipoles in a para-magnetic salt. Each has dipole moment 1.5 × 10^-23 A m². Find maximum (saturation) magnetization in the specimen.

(a)	20 A m²
(b)	30 A m²
(c)	200 A m²
(d)	50 A m²

39.

In which direction, the magnetic field on the axis at a distance z from the centre of the bar magnet would be ?

(a)	On the magnetic of the magnetic moment $(\vec{m})$ of the magnet
(b)	In the perpendicular direction of the magnetic moment $(\vec{m})$ of the magnet
(c)	In the opposite direction of the magnetic dipole moment $(\vec{m})$ of the magnet
(d)	In the direction of the magnetic dipole moment $(\vec{m})$ of the magnet

40.

Which of the following is represented by the area enclosed by a hysteresis loop (B-H curve) ?

(a) Heat energy lost per unit volume in the sample

(b) Permeability

(c) Susceptibiltiy

(d) Retentivity

Showing 31 to 40 out of 145 Questions