Friction

Front

What is friction?

Back

Friction is a contact force that opposes the motion of an object when it comes into contact with another surface.

Front

What type of force is friction?

Back

Friction is a contact force.

Front

Which of the following is an example of helpful friction?

Back

Brakes on a bike, tires on a car, and tread on shoes are all examples of helpful friction.

Front

What happens to friction on rougher surfaces?

Back

Rougher surfaces have greater friction.

Front

What is a contact force?

Back

A contact force is a force that occurs when objects are physically touching.

Front

Do rough surfaces allow objects to travel faster?

Back

False, the rougher the surface, the slower an object will travel.

Front

What is an example of friction that is not helpful?

Back

Friction between a sled and a smooth ice surface can be an example of unhelpful friction.

Front

How does friction affect motion?

Back

Friction opposes motion, making it harder for objects to slide or roll.

Front

What is static friction?

Back

Static friction is the friction that prevents an object from starting to move.

Front

What is kinetic friction?

Back

Kinetic friction is the friction that acts on an object that is already in motion.