## MCQ (Single Correct Answer)

Given below are two statements:
Statement I : The diamagnetic property depends on temperature.
Statement II : The induced magnetic dipole moment in a ...

The free space inside a current carrying toroid is filled with a material of susceptibility $$2 \times 10^{-2}$$. The percentage increase in the value...

A bar magnet is released from rest along the axis of a very long vertical copper tube. After some time the magnet will

Given below are two statements:
Statement I : For diamagnetic substance, $$-1 \leq \chi
Statement II : Diamagnetic substances when placed in an exter...

Given below are two statements: one is labelled as Assertion $$\mathbf{A}$$ and the other is labelled as Reason $$\mathbf{R}$$
Assertion A : Electroma...

A bar magnet with a magnetic moment $$5.0 \mathrm{Am}^{2}$$ is placed in parallel position relative to a magnetic field of $$0.4 \mathrm{~T}$$. The am...

A solenoid of 1200 turns is wound uniformly in a single layer on a glass tube 2 m long and 0.2 m in diameter. The magnetic intensity at the center of ...

The vertical component of the earth's magnetic field is $$6 \times 10^{-5} \mathrm{~T}$$ at any place where the angle of dip is $$37^{\circ}$$. The ea...

A compass needle of oscillation magnetometer oscillates 20 times per minute at a place $$\mathrm{P}$$ of $$\operatorname{dip} 30^{\circ}$$. The number...

Two bar magnets oscillate in a horizontal plane in earth's magnetic field with time periods of $$3 \mathrm{~s}$$ and $$4 \mathrm{~s}$$ respectively. I...

A magnet hung at $$45^{\circ}$$ with magnetic meridian makes an angle of $$60^{\circ}$$ with the horizontal. The actual value of the angle of dip is -...

An electron with energy 0.1 keV moves at right angle to the earth's magnetic field of 1 $$\times$$ 10$$-$$4 Wbm$$-$$2. The frequency of revolution of ...

At a certain place the angle of dip is 30$$^\circ$$ and the horizontal component of earth's magnetic field is 0.5 G. The earth's total magnetic field ...

The space inside a straight current carrying solenoid is filled with a magnetic material having magnetic susceptibility equal to 1.2 $$\times$$ 10$$-$...

The susceptibility of a paramagnetic material is 99. The permeability of the material in Wb/A-m, is :
[Permeability of free space $$\mu$$0 = 4$$\pi$$ ...

A bar magnet having a magnetic moment of 2.0 $$\times$$ 105 JT$$-$$1, is placed along the direction of uniform magnetic field of magnitude B
= 14 $$...

Given below are two statements :
Statement I : Susceptibilities of paramagnetic and ferromagnetic substances increase with decrease in temperature.
St...

The soft-iron is a suitable material for making an electromagnet. This is because soft-iron has

Following plots show magnetization (M) vs magnetizing field (H) and magnetic susceptibility ($$\chi $$) vs temperature (T) graph :Which of the followi...

Choose the correct option

Statement I : The ferromagnetic property depends on temperature. At high temperature, ferromagnet becomes paramagnet.Statement II : At high temperatur...

At an angle of 30$$^\circ$$ to the magnetic meridian, the apparent dip is 45$$^\circ$$. Find the true dip :

The magnetic susceptibility of a material of a rod is 499. Permeability in vacuum is 4$$\pi$$ $$\times$$ 10$$-$$7 H/m. Absolute permeability of the ma...

Which of the following statements are correct?(A) Electric monopoles do not exist whereas magnetic monopoles exist.(B) Magnetic field lines due to a s...

A bar magnet of length 14 cm is placed in the magnetic meridian with its north pole pointing towards the geographic north pole. A neutral point is obt...

In a ferromagnetic material, below the curie temperature, a domain is defined as :

A soft ferromagnetic material is placed in an external magnetic field. The magnetic domains :

A paramagnetic sample shows a net magnetisation of 6 A/m when it is placed in an external
magnetic field of 0.4 T at a temperature of 4 K. When the sa...

A small bar magnet placed with its axis at 30o with an external field of 0.06 T experiences a torque of 0.018 Nm. The minimum work required to rotate ...

A perfectly diamagnetic sphere has a small spherical cavity at its centre, which is filled with a
paramagnetic substance. The whole system is placed i...

Magnetic materials used for making permanent
magnets (P) and magnets in a transformer (T)
have different properties of the following,
which property b...

The figure gives experimentally measured B vs H variation in a ferromagnetic material. The
retentivity, coercivity and saturation, respectively, of t...

A magnetic compass needle oscillates 30 times per minute at a place where the dip is 45o, and 40 times per
minute where the dip is 30o. If B1 and B2 a...

Two magnetic dipoles X and Y are placed at
a separation d, with their axes perpendicular to
each other. The dipole moment of Y is twice
that of X. A p...

A paramagnetic material has 1028 atoms/m3. Its magnetic susceptibility at temperature 350 K is 2.8 $$ \times $$ 10–4. Its susceptibility at 300 K 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/ T when a magnetic intensity of ...

At some location on earth, the horizontal component of earth’s magnetic field is 18 × 10–6 T. At this location, magnetic needle of length 0.12 m and p...

A magnet of total magnetic moment 10-2 $${\widehat i}$$ A-m2 is placed in a time varying magnetic field, B$${\widehat i}$$ (cos $$\omega t$$) where B...

A bar magnet is demagnetized by inserting it inside a solenoid of length 0.2 m, 100 turns, and carrying a current of 5.2 A. The corecivity of the bar ...

The $$B$$-$$H$$ curve for a ferromagnet is shown in the figure. The ferromagnet is placed inside a long solended with $$1000$$ turns/cm. The current t...

A magnetic needle of magnetic moment 6.7 $$\times$$ 10-2 A m2 and moment of inertia 7.5 $$\times$$ 10-6 kg m2 is
performing simple harmonic oscillatio...

A fighter plane of length 20 m, wing span (distance from tip of one wing to the tip of the other wing) of 15 m and height 5 m is flying towards east o...

Hysteresis loops for two magnetic materials $$A$$ and $$B$$ are given below :
These materials are used to make magnets for electric generators, tran...

The coercivity of a small magnet where the ferromagnet gets demagnetized is $$3 \times {10^3}\,A{m^{ - 1}}.$$ The current required to be passed in a s...

Two short bar magnets of length $$1$$ $$cm$$ each have magnetic moments $$1.20$$ $$A{m^2}$$ and $$1.00$$ $$A{m^2}$$ respectively. They are placed on ...

Relative permittivity and permeability of a material $${\varepsilon _r}$$ and $${\mu _r},$$ respectively. Which of the following values of these quant...

Needles $${N_1}$$, $${N_2}$$ and $${N_3}$$ are made of ferromagnetic, a paramagnetic and a diamagnetic substance respectively. A magnet when brought c...

A magnetic needle is kept in a non-uniform magnetic field. It experiences :

Curie temperature is the temperature above which

The length of a magnet is large compared to its width and breadth. The time period of its oscillation in a vibration magnetometer is $$2s.$$ The magne...

The materials suitable for making electromagnets should have

A thin rectangular magnet suspended freely has a period of oscillation equal to $$T.$$ Now it is broken into two equal halves (each having half of the...

A magnetic needle lying parallel to a magnetic field requires $$W$$ units of work to turn it through $${60^ \circ }.$$ The torque needed to maintain t...

The magnetic lines of force inside a bar magnet

## Numerical

A compass needle oscillates 20 times per minute at a place where the dip is $$30^{\circ}$$ and 30 times per minute where the dip is $$60^{\circ}$$. Th...

The current required to be passed through a solenoid of 15 cm length and 60 turns in order of demagnetise a bar magnet of magnetic intensity $$2.4\tim...

The magnetic intensity at the center of a long current carrying solenoid is found to be $$1.6 \times 10^{3} \mathrm{Am}^{-1}$$. If the number of turns...

In a uniform magnetic field, the magnetic needle has a magnetic moment 9.85 $$\times$$ 10$$-$$2 A/m2 and moment of inertia 5 $$\times$$ 10$$-$$6 kg m2...

The value of aluminium susceptibility is 2.2 $$\times$$ 10$$-$$5. The percentage increase in the magnetic field if space within a current carrying tor...