What is a diamagnetic material? Give two examples.

Explanation

### Step-by-Step Solution:

1. **Definition of Diamagnetic Material**:
A diamagnetic material is defined as a substance that exhibits a very weak and negative magnetic response when exposed to an external magnetic field. This means that in the absence of a magnetic field, these materials do not have any net magnetic moment.

2. **Behavior in Magnetic Field**:
When a diamagnetic material is placed in a uniform magnetic field, it develops a magnetic moment that is opposite to the direction of the applied magnetic field. This results in a repulsive effect, causing the diamagnetic material to be pushed away from the magnetic field.

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