1. The Force of Friction Friction opposes motion between two surfaces that touch each other. The amount of friction depends on.....

2. Surface Roughness

3. Forces pushing the two surfaces together.

4. Types of Friction https://app.discoveryeducation.com/player/view/assetGuid/72E28A59-0EAB- 4EC9-A097-365513460023

5. Static Friction: A force is applied, but the object does not move. All of the forces are balanced.

6. Kinetic Friction (unbalanced forces - motion occurs) Sliding Friction http://www.explorelearning.com/index.cfm?method=cResource.dspView&ResourceID=27

7. Rolling Friction http://www.explorelearning.com/index.cfm?method=cResource.dspView&ResourceID=587

8. Walking Writing Friction Can be Helpful!!

9. Sanding an Icy Road Wearing Batting Gloves

10. Using Rosin

11. Fluid Friction Adding lubricants decreases friction and prevents engine parts from wearing down.

12. More Fluid Friction... air and water

13. Sometimes friction can be harmful and must be reduced.

14. Such as Erosion !

15. How is this friction Helpful?

16. Zamboni Machines smooth the ice. Sanding Wood

17. Using ball bearings reduces friction within the wheel.

18. How did friction do this?? Why does the surfer wax his board?