If the magnet is cut into four equal parts such that their lengths and breadths are equal . Pole strength of each part is

Options

A. m
B. m/2
C. m/4
D. m/8

Explanation

To solve the problem of determining the pole strength of each part when a magnet is cut into four equal parts, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Pole Strength**:
- The pole strength (M) of a magnet is a measure of the strength of its magnetic poles. It is directly proportional to the area of the magnet.

2. **Cutting the Magnet**:
- When the magnet is cut into four equal parts, we need to consider how the cuts are made. The problem states that the cuts are made such that the lengths and breadths are equal. This implies that we are cutting the magnet into smaller rectangular pieces of equal size.

3. **Area Reduction**:
- Each cut will reduce the area of the magnet. If the original magnet has an area A, cutting it into four equal parts will result in each part having an area of A/4.

4. **Pole Strength Calculation**:
- Since the pole strength is directly proportional to the area, if the area of each part is A/4, the new pole strength (P) of each part can be calculated as:
\[ P = \frac{M}{4} \]
- This means that the pole strength of each part is one-fourth of the original pole strength.

5. **Conclusion**:
- Therefore, the pole strength of each part after cutting the magnet into four equal parts is \( \frac{M}{4} \).

### Final Answer:
The pole strength of each part is \( \frac{M}{4} \).