In each of the following situations state what effect the change will have on friction using the following choices:
A. Increase
B. Decrease
C. No change


___1. The normal force increase.

___2. The speed of the object changes from 10 m/s to 20 m/s.

___3. The speed of the object changes from 0 m/s to 20 m/s

___4. The roughness of only one surface is increased.

___5. The surface area in contact increases.

___6. A lubricant is added between the surface.

___7. Ur changes to uk

___8. Two pieces of rubbing metal are moved from earth to outer space.

___9. Applying floor wax in a classroom.

___10. Gymnasts apply more coarse substance on their hands.