Question

A diamagnetic substance produces a
A. Strong magnetic field in opposition of an externally applied magnetic field
B. Weak magnetic field in the direction of an externally applied magnetic field
C. Weak magnetic field in opposition of an externally applied magnetic field
D. Strong magnetic field in the direction of an externally applied magnetic field.

Answer 1

Hint: In this question, we need to understand the effect of diamagnetic substance in presence of an external magnetic field. Mention the susceptibility of diamagnetic substance. Diamagnetic substances have net dipole of zero as there is complete pairing of between the electrons.

Complete answer:
For this question let us define what diamagnetic substances are. Let us understand how diamagnetic substances behave in magnetic fields and whether their susceptibility is positive, negative or zero.Let us first understand what magnetic substances are, magnetic substances are ones which can be magnetized and are strongly attracted to a magnet. Some common magnetic substances are elements such as iron, cobalt, nickel, etc.

Diamagnetic substances are those substances that are easily magnetized in the opposite direction when placed in a magnetic field. They are repelled in a magnetic field. The net dipole is zero due to pairing between the electrons. In an external magnetic field, the dipoles are induced in the diamagnetic materials in such a way that induced dipoles oppose the external magnetic field therefore, all the materials whose atoms contain paired electrons show diamagnetic properties.When such a diamagnetic substance is brough in the influence of a magnetic field, it produces a weak magnetic dipole moment and thus a weak magnetic field in the opposite direction.

Thus, option B is the correct option.

Note:Unlike most magnetic substances, diamagnetic substances repel when placed in a magnetic field. The diamagnetism property is present in all materials and it is independent of temperature. Diamagnetism is possible in all three states that is in solid, liquid and gas.Some more examples of diamagnetic substances are Silver, Carbon, Zinc, Bismuth, Gold, Antimony, Marble and water.