1) A force is: a) another word for friction b) stored energy c) measured in kilograms d) a push, pull or twist. 2) While surfing, drag acts to a) slow the surfer down b) increase the speed of the surfer c) keep the surfboard afloat d) stop the surfer’s feet from slipping off the surfboard 3) Friction between two surfaces is greatest when the two surfaces are: a) smooth and they are gently pressed together b) rough and they are gently pressed together c) smooth and they are pressed together firmly d) rough and they are pressed together firmly. 4) Lubricants help reduce friction by a) filling in the spaces between surfaces b) keeping surfaces clean c) keeping surfaces shiny d) removing rough edges. 5) Which of the following is not an example of a force in action? a) an archer stretching a bow. b) the sun shining onto a rainforest. c) a car rolling down a hill. d) a person rowing a boat on a lake. 6) An example of a contact force is: a) a magnet which helps to close a fridge door. b) electrical interference on your car radio. c) a tennis player serving the ball. d) gravity on the moon. 7) An example of a non-contact force is: a) hitting a cricket ball with a bat. b) using your bicycle brakes. c) two teams having a tug-of-war with a rope. d) a person falling out of a tree. 8) When the forces acting forwards on a bicycle are equal to the forces acting backwards, the cyclist and his cycle will: a) speed up. b) slow down. c) come to a stop. d) continue at the same speed.

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