PHYSICS MID TERM

The amount of friction depends on the weight of the objects pressing together.

• True
• False

How does friction affect speed?

• more friction decreases speed
• more friction increases speed
• less friction decreases speed
• less friction doesn't affect speed

What is friction?

• It is a resistance force
• Friction  does not exist
• It is an imaginary force
• It is red

Which of the following is an example of friction that is helpful?

• Brakes used on a bike
• Tires from a car on the road
• Tread on the bottom of your shoes
• All are examples that are helpful

Friction is a force that acts in a(n) ___________ direction relative to a moving object.

• similar
• opposite
• parallel
• perpendicular

What does friction produce?

• light
• sound
• heat
• gravity

How do you lower the friction force?

• By a smooth surface
• By a rough surface
• By not pushing hard
• By pushing down

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 a constant speed.

Friction is an example of _____________

• contact force

• non contact force

• both of these

• none of these

Without friction, an object in motion would never stop.

• true

• false