1) The force that occurs when an object rubs against another object is called.......... a) friction. b) gravity. c) push. d) pull. 2) The force that tries to stop an object moving on a surface is called.......... a) gravity. b) friction. c) push. d) pull. 3) There is a...........force between the car tires and the road that acts to decrease the car speed gradually. a) gravity b) pulling c) pushing d) friction 4) Which of the following sentenses describes the friction force? a) It pulls objects toward the ground. b) It pushs objects away from the ground. c) It slows down or stops objects in motion. d) It does not affect objects in motion. 5) When an apple falls from a tree down to the ground, it is affected by........... a) friction force of air only. b) gravity pulling force only. c) gravity pushing force only. d) friction of air and gravity pulling forces. 6) Tamer pushes a ball on a flat ground and it covers a distance of 30 cm. If he pushes it with more force, it may cover a distance equal to.........cm. a) 5 b) 15 c) 30 d) 50

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