A diamagnetic substance is brought near a strong magnet, then it is

Options

A. attracted by a magnet
B. repelled by a magnet
C. repelled by North pole and attracted by South pole
D. attracted by North pole and repelled by South pole

Answer

To solve the question about the behavior of a diamagnetic substance when brought near a strong magnet, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Diamagnetism**:
- A diamagnetic substance is characterized by its weak negative susceptibility to magnetic fields. This means that it is repelled by a magnetic field.

2. **Magnetic Field of a Strong Magnet**:
- A strong magnet generates a magnetic field with distinct field lines. The direction of these field lines indicates the strength of the magnetic field, which is stronger near the poles of the magnet (North and South).

3. **Behavior of Diamagnetic Substances in a Magnetic Field**:
- When a diamagnetic material is placed in a magnetic field, it will experience a force that causes it to move from regions of stronger magnetic field to regions of weaker magnetic field. This is due to the induced magnetic moment in the diamagnetic material, which opposes the external magnetic field.

4. **Proximity to the Magnet**:
- As the diamagnetic substance is brought closer to the strong magnet, it will find itself in a region where the magnetic field is stronger. Since diamagnetic materials are repelled by magnetic fields, they will move away from the stronger field towards the weaker field.

5. **Conclusion**:
- Therefore, when a diamagnetic substance is brought near a strong magnet, it is repelled by both the North and South poles of the magnet. It does not get attracted to either pole.

### Final Answer:
The diamagnetic substance is repelled by both the North and South poles of the magnet.