Friction and Air Resistance

Which is the best description of the purpose of a lubricant?

• Reduces the amount of friction and increases the amount of thrust

• Reduces the amount of friction and increases useful energy transfer

• Reduces wasteful energy transfer and increases the amount of thrust

How does friction affect speed?

• more friction decreases speed

• more friction increases speed

• less friction decreases speed

Air resistance is a type of friction.

• True

• False

Friction is ___________

• Only when 2 things rub together

• An example of gravity

• When the planets revolve around the sun.

• A force that opposes motions of an object.

If you are moving heavy furniture and want to reduce friction, what could you do?

• Get strong to make it easier to pick up.

• Put a blanket under it and slide it.

• Add water to the floor.

Why does a feather fall through the air more slowly than a bowling ball?

• Feathers come from birds so they can fly.

• Air resistance

• I don't know.

Tags

NGSS.MS-PS2-2

Planes are built to have a pointed end in order to fly more easily through the air. What are they trying to combat when flying?

• Gravity

• Birds

• Air Resistance

• Clouds

Tags

NGSS.MS-ETS1-1

NGSS.MS-ETS1-2

Friction is a force that acts in an ___________ direction of movement.

• similar

• opposite

• parallel

• west

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