There are two magnets P and T, P is used as permanent magnet while T is used in transformers. Then correct options are

Options

A. P has high retentivity and low coercivity
B. P has low retentivity and high coercivity
C. T has low coercivity and low retentivity
D. T has high coercivity and high retentivity

Answer

To solve the problem, we need to analyze the properties of the two magnets, P and T, based on their applications.

### Step-by-Step Solution:

1. **Understanding the Magnets**:
- Magnet P is a permanent magnet.
- Magnet T is used in transformers.

2. **Defining Key Terms**:
- **Retentivity**: This is the ability of a material to retain magnetism after the external magnetic field is removed. High retentivity means the material retains a significant amount of magnetism.
- **Coercivity**: This is the measure of the resistance of a ferromagnetic material to becoming demagnetized. High coercivity means a strong magnetic field is required to demagnetize the material.

3. **Analyzing Magnet P (Permanent Magnet)**:
- Permanent magnets are designed to retain their magnetism over time. Therefore, they have:
- **High Retentivity**: They retain a significant amount of magnetism.
- **High Coercivity**: They require a strong magnetic field to demagnetize.

4. **Analyzing Magnet T (Used in Transformers)**:
- In transformers, the magnetic material is subjected to alternating magnetic fields. Therefore, it should not retain magnetism after the field is removed. Hence, it has:
- **Low Retentivity**: It does not retain significant magnetism.
- **Low Coercivity**: It can be easily demagnetized.

5. **Evaluating the Options**:
- **Option 1**: P has high retentivity and low coercivity. (Incorrect, coercivity is high)
- **Option 2**: P has low retentivity. (Incorrect, retentivity is high)
- **Option 3**: T has low coercivity and low retentivity. (Correct)
- **Option 4**: (Not specified, but based on previous analysis, it is likely incorrect)

6. **Conclusion**:
- The correct option is **Option 3**, which states that T has low coercivity and low retentivity.