Friction

[|Yoyo Friction Veritasium]

Air Bearings Turbine Engines

Phone book friction Myth Busters https://www.youtube.com/watch?v=QMW_uYWwHWQ

Two Column Notes

Focus Question: What is the advantage of anti-lock brakes?

1. A force is a push or a pull.

2. Forces have a magnitude and a direction.

3. Magnitude is the amount of force.

4. Friction is a force that two surfaces exert on each other when they rub against each other.

5. Friction depends on the type of surfaces involved and how hard the surfaces are pushed together.

6. Static Friction (Stationary) - occurs between surfaces that are not moving. (Greatest in strength) (Non-skidding tire)

7. Sliding Friction - occurs between surfaces as they slide. (Much weaker than static friction) (Skidding tire)

8. Rolling Friction - occurs when one surface rolls across another.

9. Friction magnified: a) Interlocking high points make static friction the strongest. . b) High points sliding past each other, rather than interlocking, makes sliding friction much less than static friction. . c) High points lower and raise in rolling friction making friction much lower. . 10.Fluid friction - occurs when a solid object moves through a fluid. (Such as water or oil on a road.)

11. Unbalanced forces - can cause the velocity of an object to change. (Applying the brakes in a car.)

12. Balanced forces - do not cause the velocity of an object to change. (Car on cruise control - force of the engine balances the force of friction.)

13. Net Force - all the forces on an object combined.



[|Very High Levels of Friction]

Song

Slippery Science