In what way is the behaviour of a diamagnetic material different from that of a paramagnetic material, when kept in an external magnetic field?

Explanation

To understand the behavior of diamagnetic and paramagnetic materials in an external magnetic field, we can break down the differences into several key points:

### Step-by-Step Solution:

1. **Definition of Diamagnetic and Paramagnetic Materials**:
- **Diamagnetic Materials**: These materials have no unpaired electrons and are characterized by a negative magnetic susceptibility. They are repelled by magnetic fields.
- **Paramagnetic Materials**: These materials have unpaired electrons and possess a positive magnetic susceptibility. They are attracted to magnetic fields.

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