Soft iron is preferred as the core of a transformer in the form of sheets due to its

Options

A. Low retentivity, low coercivity and low hysteresis loss
B. High retentivity, high coercivity and low hysteresis loss
C. Low retentivity, low coercivity and high hysteresis loss
D. Low retentivity, high coercivity and high hysteresis loss

Answer

To solve the question regarding why soft iron is preferred as the core of a transformer in the form of sheets, we can break down the reasoning into several key points.

### Step-by-Step Solution:

1. **Understanding the Core Material**:
- The core of a transformer is crucial for its efficiency. It needs to be made of a material that can easily magnetize and demagnetize.

2. **Properties of Soft Iron**:
- Soft iron has specific magnetic properties that make it suitable for transformer cores:
- **Low Hysteresis Loss**: Soft iron exhibits low hysteresis loss, which means that when the magnetic field is cycled (magnetization and demagnetization), the energy lost due to heat is minimal. This is important for efficiency.
- **Low Coercivity**: Soft iron has low coercivity, meaning it requires a small amount of magnetizing force to demagnetize. This allows for quick changes in magnetization, which is essential for alternating current (AC) applications in transformers.
- **High Permeability**: Soft iron has high magnetic permeability, allowing it to conduct magnetic lines of force effectively.

3. **Use of Sheets**:
- The core is often made of thin sheets of soft iron (laminations) to reduce eddy current losses. Eddy currents are loops of electric current induced within conductors by a changing magnetic field. By using thin sheets, the area for these currents is minimized, thus reducing energy loss.

4. **Conclusion**:
- Therefore, soft iron is preferred as the core of a transformer because it has low hysteresis loss, low coercivity, and can be made into thin sheets to minimize eddy current losses.

### Final Answer:
Soft iron is preferred as the core of a transformer in the form of sheets due to its low hysteresis loss, low coercivity, and the ability to reduce eddy current losses through lamination.