Across
- 4. A material often used to increase friction (8 letters)
- 6. Frictional force that acts between surfaces in contact and at rest (7 letters)
- 7. The force that opposes motion (7 letters)
Down
- 1. Type of friction between a wheel and a surface (8 letters)
- 2. The device used to reduce friction between moving parts (6 letters)
- 3. Frictional force that acts between surfaces in motion (8 letters)
- 5. are the crossword clues along with their answers:
- 8. The roughness of a surface affects this (8 letters)