a soap bubble is given positive charge, then its radius.

Options

A. Decreases
B. Increases
C. Remains unchanged
D. Nothing can be predicted as information is insufficient.

Answer

To solve the problem of how a soap bubble behaves when given a positive charge, we can break down the solution into several steps:

### Step-by-Step Solution:

1. **Understanding the Soap Bubble**:
- A soap bubble is a thin film of liquid (soap solution) that forms a spherical shape due to surface tension.

2. **Applying Charge to the Bubble**:
- When a positive charge is given to the soap bubble, this charge distributes uniformly over the surface of the bubble.

3. **Effect of Charge on Charges**:
- The positive charges on the surface of the bubble will repel each other due to electrostatic repulsion. This is because like charges repel.

4. **Resulting Forces**:
- Each charge on the surface exerts a repulsive force on every other charge. This repulsion acts outwardly, causing the bubble to try to expand.

5. **Change in Radius**:
- To counteract the repulsive forces among the charges, the bubble will expand, which means its radius will increase.

6. **Conclusion**:
- Therefore, when a soap bubble is given a positive charge, its radius increases.

### Final Answer:
The radius of the soap bubble will **increase** when it is given a positive charge.

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