1. Lesson 2
Controlling Friction

2. Friction can be either an advantage or a disadvantage, depending on the situation. Unwanted friction can be reduced when needed while friction can be added if needed.

3. Methods of reducing friction
Ball bearings reduce friction and are often used in wheels of all sorts.

4. Lubricants such as grease and oil can help reduce friction and wear

5. A layer of air between objects can greatly reduce friction
A layer of air between objects can greatly reduce friction. Hovercraft and air hockey tables use this method.

6. Reasons for increasing friction
Friction is needed in order for us to move safely, Friction is designed into highways, tires, athletic shoes, and brakes

7. Coefficients of friction lab
Coefficients of friction are determined by experiments rather than calculations. In this investigation, you will measure FSmax and FK for a block being pulled on several surfaces. You will then apply the equations for static and kinetic friction to determine the coefficients of friction in each situation. The applied force acting on the block should always be parallel to the surface.