_______have less irregularities which leads to less interlocking between the two surfaces, thus requiring a lesser force to break these interlock.

Options

A. smooth surfaces
B. Rough surfaces
C. Plain surfaces
D. None of them

Answer

To solve the question, we need to identify the type of surfaces that have fewer irregularities, which results in less interlocking between the two surfaces. This reduced interlocking means that a lesser force is required to overcome the friction between them.

### Step-by-Step Solution:

1. **Understanding Surface Irregularities**:
- Surfaces can be classified based on their texture. Some surfaces are smooth, while others are rough.
- Smooth surfaces have fewer irregularities, meaning they are more even and flat.

2. **Interlocking of Surfaces**:
- When two surfaces come into contact, their irregularities can interlock. This interlocking is what creates friction.
- On rough surfaces, the irregularities are more pronounced, leading to greater interlocking.

3. **Force Required to Break Interlocking**:
- The amount of force needed to break the interlocking between two surfaces depends on how much they interlock.
- For smooth surfaces, since there are fewer irregularities and less interlocking, less force is required to overcome the friction.

4. **Conclusion**:
- Therefore, the type of surfaces that have less irregularities, leading to less interlocking and requiring lesser force to break these interlocks, are called **smooth surfaces**.

### Final Answer:
Smooth surfaces have less irregularities which leads to less interlocking between the two surfaces, thus requiring a lesser force to break these interlocks.

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