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Physics · Mechanics · Friction
Friction on an inclined plane
Place a block on a tilted plank and slowly raise one end. At the angle where the block JUST begins to slide, the static-friction force has been overcome. Use μs = tan θ to find the coefficient of static friction for each pair of surfaces.
angle θ
5.0°
Results table
| Surface | θ (°) | μs = tan θ |
|---|---|---|
| Polished wood | — | — |
| Wood on wood | — | — |
| Rubber on wood | — | — |
| Wood on sandpaper | — | — |
Exam-style questions
1. At the angle when the block just BEGINS to slide, what is the relationship between angle and coefficient of static friction?
2. Why is the coefficient of friction for RUBBER on wood the highest?
3. Once the block starts to slide, friction is generally:
4. Which of these would NOT affect the slipping angle (same surfaces)?