1) What is free fall? a) When the only unbalanced force acting on a falling object is gravity. b) When gravity is not acting on an object c) When a object is floating through space d) When nobody is touching the object 2) Near the surface of earth, the acceleration of gravity is __. a) 9.8/s² b) 90/s² c) 30/s² d) 5.5/s² e) 6.9/s² 3) What is acceleration? a) When something is speeding up b) When something is slowing down c) When something is in space d) When something is nonexistent 4) What is air resistance? a) Objects falling through the air experience a type of fluid friction b) Objects in air explode c) objects in air shoot up into space 5) Air resistance ___ with velocity. a) increases b) decreases c) breaks down 6) If you drop two objects at the same position it will not fall the same way. a) True b) False c) It depends 7) When something is decelerating it is __. a) slowing down b) speeding up 8) When something is accelerating its ___ a) speeding up b) slowing down 9) Who "Discovered gravity" a) Sir Isaac Newton b) Me c) John Tailigman d) Amy Newton

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