Friction

Lilly has a flat piece of paper and a ball of paper. She drops both papers at the same time from the same height. The ball of paper hits the ground first. Which force acts on the flat piece of paper that slows it down?

• friction
• gravity
• inertia
• magnetism

Movers slide a box down the ramp of a truck.
What helps slow the box as it slides to the bottom of the ramp?

• friction
• gravity
• inertia
• magnetism

A man is pushing a ball up a hill. If the man stops pushing the ball and steps out of the way, what will most likely happen to the ball?

• It will stop on the hill.
• It will roll down the hill.
• It will roll to the side toward the man.
• It will fly.

How would the absence of friction affect a marble traveling on a long, straight path?

• The marble’s speed would decrease.
• The marble’s speed would increase.
• The marble would stop immediately. 
• The marble would remain at constant speed.

What causes a ball to move through the air when it is thrown?

• heat
• force
• friction
• gravity

Why is it important for basketball players to wear shoes with tread when playing?

• to increase the speed of the player
• to decrease the force between the player and the floor
• to increase friction between the floor and the player’s feet
• to decrease the amount of force needed for the player to move

Which best describes the role friction plays in the operation of a car?

• Friction makes a car go faster.
• Friction keeps a car from stopping.
• Friction turns the car in a new direction.
• Friction helps a car slow down and stop.

John stands at the top of a steep hill and pushes a ball over the edge with his foot. Which force causes the ball to continue rolling down the hill?

• mass
• gravity
• friction
• air resistance

Which would make a car move fastest?

• moving up a steep slope
• moving up a gradual slope
• moving down a steep slope
• moving down a gradual slope

Which material should be used on a bicycle ramp to increase friction?

• shiny metal
• rough paper
• smooth wood
• wet plastic