The magnetic susceptibility is negative for

Options

A. paramagnetic materials only
B. diamagnetic materials only
C. ferromagnetic materials only
D. paramagnetic and ferromagnetic materials.

Answer

To solve the question regarding the magnetic susceptibility being negative, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Magnetic Susceptibility**:
- Magnetic susceptibility (χ) is a measure of how much a material will become magnetized in an external magnetic field. It indicates whether a material is attracted to or repelled by a magnetic field.

2. **Identify the Types of Magnetic Materials**:
- There are three main types of magnetic materials:
- **Diamagnetic**: Materials that are weakly repelled by a magnetic field.
- **Paramagnetic**: Materials that are weakly attracted by a magnetic field.
- **Ferromagnetic**: Materials that are strongly attracted by a magnetic field.

3. **Determine the Sign of Magnetic Susceptibility**:
- For diamagnetic materials, the magnetic susceptibility is negative (χ < 0).
- For paramagnetic and ferromagnetic materials, the magnetic susceptibility is positive (χ > 0).

4. **Conclusion**:
- Since the question states that the magnetic susceptibility is negative, we conclude that the material in question must be a **diamagnetic material**.

### Final Answer:
The magnetic susceptibility is negative for **diamagnetic materials**.

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