Contact Forces

Contacts forces:

• These are forces between objects that are physically touching each other.

• Examples include:

  Pushing a desk or pulling a go-cart

Friction:

• Force exerted on a slowing ball.

• Friction force act in the opposite direction to the object’s motion.

• If the ball is moving forward, friction acts backwards.

Factors affecting force requirement:

• The force required depends on all forces acting on an object.

• The force of friction depends on the surface type and normal force.

• To overcome friction, a force greater than the friction force is needed.

  Advantages of friction:

• Enables forward movement and prevents slipping, and helps cars not to skid.