Which of these is not a contact force?

If the forces acting on an object are balanced, the object will...

When you rub your hands together, which force is acting?

Friction produces...

You can reduce friction by making the surfaces...

Rougher surfaces create __________ friction.

Which of these scenarios would you expect more friction?

If the amount of friction increased, what would you expect to happen to the amount of heat?

Friction works in the _____________ direction to the object moving.