Which of the following statements related to magnetic materials are correct?

A. Diamagnetic materials get strongly magnetized in an external magnetic field.

B. Ferromagnetic materials get strongly magnetized in an external magnetic field.

C. Paramagnetic materials get weakly magnetized in an external magnetic field.

D. Soft iron is a suitable material for the core of electro-magnets.

E. For diamagnetic materials, magnetic susceptibility is positive and small.

Choose the correct answer from the options given below:

B, C, D only

The measurement of how much a magnetic material will be magnetized in a given magnetic field is called magnetic susceptibility. It is denoted by χ. 

1. Magnetic susceptibility is the ratio of magnetization and the applied magnetizing field intensity. Magnetic Susceptibility (χ) = Magnetization/magnetizing field intensity

2. Paramagnetic materials: for paramagnetic materials, magnetic susceptibility is inversely proportional to the temperature. Paramagnetic materials get weakly magnetized in an external magnetic field.

3. Diamagnetic materials: it has a magnetic susceptibility χ < 0 i.e. negative.

4. A change in temperature can only affect the random thermal motion of the atom. Since each atom of a diamagnetic substance has zero magnetic dipole moment, the temperature cannot affect the net magnetic moment in any way.

5. Diamagnetic substances are independent of temperature. Therefore, magnetic susceptibility remains constant irrespective of the temperature.

6. Effect of Temperature Ferromagnetism:The magnetic susceptibility decreases with an increase in temperature. So, the ferromagnetism decreases with rising temperature.

7. Ferromagnetic materials get strongly magnetized in an external magnetic field.

8. The core of electromagnet is made of soft iron.