Choose the correct option for each question. There is only one correct response for each question.
Which type of friction would have the greatest magnitude?

Options

A. Moving
B. Sliding
C. Rolling
D. Static

Answer

To determine which type of friction has the greatest magnitude, we need to analyze the different types of friction: static friction, sliding (or kinetic) friction, and rolling friction.

### Step-by-Step Solution:

1. **Understanding Friction Types**:
- **Static Friction**: This is the friction that acts on an object at rest. It prevents the object from starting to move. It can vary in magnitude up to a maximum value.
- **Sliding (Kinetic) Friction**: This occurs when two surfaces slide against each other. It is usually less than the maximum static friction.
- **Rolling Friction**: This occurs when an object rolls over a surface. It is generally the least among the three types of friction.

2. **Analyzing Interlocking of Surfaces**:
- Friction arises due to the interlocking of microscopic irregularities on the surfaces in contact.
- In static friction, the object has time to settle and interlock its irregularities, leading to a higher frictional force.

3. **Comparing Magnitudes**:
- Static friction has the highest magnitude because it can adjust to the maximum interlocking of surface irregularities before motion starts.
- Sliding friction has a lower magnitude because the points of contact are constantly changing, preventing full interlocking.
- Rolling friction has the least magnitude as the contact area is minimal, and the rolling motion reduces the interlocking effect.

4. **Conclusion**:
- Based on the analysis, static friction has the greatest magnitude compared to sliding and rolling friction.

### Final Answer:
**Static friction** has the greatest magnitude.

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