Friction Review

What is friction?

• how fast an object is moving

• a force that opposes motion between two surfaces that are touching

• a push or pull on an object

• the rate at which velocity changes

What kind of friction do you experience when you are roller blading?

• rolling friction

• sliding friction

• fluid friction

• static friction

How can you increase friction?

• make the surface smoother

• use a lucbricant

• make the surface rougher

• put wheels on the object

What two factors affect friction?

• height and weight of object

• size and roughness of surface

• pressure and net force

• roughness of surface and weight of objects

Which type of friction affects objects that roll?

• rolling

• sliding

• fluid

• static

Which type of friction affects objects that slide over one another?

• static

• rolling

• fluid

• sliding

In which way does the force of friction act on an object?

• in the same direction as the force

• in a perpendicular direction to the force

• in the opposite direction of the force

• it doesn't matter

Which of the following examples is a "helpful" example of friction?

• a rug burn

• starting a fire

• wearing down shoes

• holes in clothing

Which of the examples shown is a "harmful" example of friction?

• erosion/weathering

• keeping things in place

• sanding wood

• brakes on a car

Fluid friction occurs when...

• an object rolls across a surface

• an object moves through a gas or a liquid

• an object slides on the ground