Froggy Jumps Gravity and Friction QuizOnline version Test your knowledge on gravity and friction forces with this quiz game! by Hayat Shammout 1 What force opposes the motion of an object sliding on a surface? a Gravity b Friction c Both 2 Which force pulls objects towards the center of the Earth? a Friction b Gravity c Both 3 What is the unit of measurement for force? a Newton b cm c Apple 4 What force keeps a car tires gripping the road? a Magnetic b Gravity c Friction 5 What force causes a book to stay on a table? a Gravity b - c Friction 6 What force allows a ball to roll down a slope? a Gravity b Friction c Magnetic