Tag: magnetic materials

Questions Related to magnetic materials

Susceptibility is large and positive for

  1. para magnetic

  2. diamagnetic

  3. ferro magnetic

  4. electromagnetic


Correct Option: C
Explanation:

Diamagnetic          Paramagnetic             ferromagnetic
-1 $\leq$ $\chi$ < 0            0 < $\chi$ < $\varepsilon$                 $\chi$ >>1
$\chi $$=$magnetic susceptibility

The core of electromagnet is made of soft iron, because
a) susceptibility of soft iron is very high
b) coercivity of soft iron is very low

  1. only a is correct

  2. only b is correct

  3. both a and b are correct

  4. both a and b are wrong


Correct Option: C
Explanation:
Because the suceptibility of the soft iron is very high. and its coercivity is very low,it is very less corrosive. 
$\chi$ >> 1 (Because it is a ferromagnetic substance.)

The value of susceptibility for super conductor is

  1. 0

  2. $\infty $

  3. +1

  4. -1


Correct Option: D
Explanation:

-1, Because superconductor are perfect diamagnetic substances.

Susceptibility is positive and large for a

  1. paramagnetic substance

  2. ferromagntic substance

  3. diamagnetic substance

  4. non magnetic substance


Correct Option: B
Explanation:

For ferromagnetic substances, $\chi _m$ is large and positive.

A superconductor exhibits perfect:

  1. ferrimagnetism

  2. ferromagnetis

  3. paramagnetism

  4. diamagnetism


Correct Option: D
Explanation:

A superconductor exhibits perfect diamagnetism.

The magnetic materials having negative magnetic susceptibility are

  1. non-magnetic

  2. para magnetic

  3. dia magnetic

  4. ferro magnetic


Correct Option: C
Explanation:

Magnetic susceptibility is a dimensionless proportionality constant that indicates the degree of magnetisation of a material in response to an applied magnetic field.

Substances such as copper, iron have negative susceptibility as these substances are diamagnetic substances.
Substances with negative susceptibility signifies that they are repelled by magnets.

Which of the following group is diamagnetic?

  1. Copper, hydrogen, silver

  2. Copper, hydrogen, argon

  3. Hydrogen, oxygen, argon

  4. Copper, silver, oxygen


Correct Option: A
Explanation:

Diamagnetic substances are those which are freebly repelled by the magnetic field.
$\therefore$ Copper, Hydrogen, Silver are diamagnetic as their atoms have net magnetic dipole moment zero.

The inherent property of all materials is

  1. Diamagnetism

  2. Paramagnetism

  3. Ferromagnetism

  4. Both a and b


Correct Option: A
Explanation:

Diamagnetism (where orbital motion of electrons creates tiny atomic current loops, which produce magnetic fields) is a property of all materials and opposes applied magnetic fields, but is very weak.

A thin diamagnetic rod is placed vertically between the poles of an electromagnet. When the current in the electromagnet is switched on, then the diamagnetic rod is pushed up, out of the horizontal magnetic field. Hence the rod gains gravitational potential energy. The work required to do this comes from.

  1. The lattice structure of the material of the rod

  2. The current source

  3. The induced electric field due to the changing magnetic field

  4. The magnetic field


Correct Option: B
Explanation:

Here when electromagnet is connected to battery, emf source the magnetic field is produced which pushes rod upwards and so gravitational potential energy is stored.

This stored energy will require work which will come from current source or battery which is connected to electromagnet.
So option 2 is correct answer

A paramagnet magnet behaves like a solenoid because both contain currents in the form of

  1. Circles

  2. Parabola

  3. Straight line

  4. Ellipse


Correct Option: A
Explanation:

A paramagnet magnet behaves like a solenoid because both contain currents in the form of circle. The magnetic field is generated by the circular motion of the electron inside the atom.