2. Friction A force that opposes motion. It occurs whenever 2 surfaces rub against each other. Friction occurs in our everyday life.

3. Advantages Friction enables an object to be held. Enables matches to be lighted. Enables us to slow down or stop a vehicle. Enables a ladder to lean against a wall. Enables us to walk without slipping. Enables us and objects to lean on the wall for support.

5. Disadvantages Friction produces heat. Friction opposes or slows down movement. Friction wears out surfaces.