A large magnet is broken into two pieces,so that their length are in the ratio 2:1.The pole strength of the two piece will be in the ratio

Options

A. `4:1`
B. `2:1`
C. `1:2`
D. `1:1`

Explanation

To solve the problem, we need to understand the concept of pole strength in magnets and how it behaves when a magnet is cut into pieces.

### Step-by-Step Solution:

1. **Understanding the Magnet**:
- A magnet has two poles: a north pole and a south pole. The strength of these poles is referred to as pole strength (denoted as 'p').

2. **Cutting the Magnet**:
- The problem states that a large magnet is broken into two pieces in the ratio of their lengths as 2:1. This means if the length of the first piece is 2x, the length of the second piece will be x.

3. **Effect of Cutting on Pole Strength**:
- When a magnet is cut into two pieces, if the cut is made perpendicular to its length, the pole strength of each piece remains the same as that of the original magnet. This is a key point in understanding the behavior of pole strength.

4. **Conclusion on Pole Strength**:
- Since both pieces are cut perpendicular to their lengths, the pole strength of both pieces will remain unchanged. Therefore, the pole strength of the first piece (2x) will be equal to the pole strength of the second piece (x).

5. **Ratio of Pole Strength**:
- Since both pieces have the same pole strength, the ratio of their pole strengths will be 1:1.

### Final Answer:
The ratio of the pole strength of the two pieces will be **1:1**.

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