Frictional Force

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

Rougher surfaces have ...

• greater friction
• less friction
• the same level of friction

 What is the unit called that measures force?

• weight
• meter
• Newton
• kilogram

What are 2 factors that determine the amount of friction between 2 objects?

• Force and roughness between surfaces
• hills and valleys and how smooth or rough the surface is
• Amount of force and amount of surface the comes in contact
• The force and the weight exerted on the surfaces

The picture shows a boy pulling

a box. How can he move the box

more easily?

• Using wooden rollers.

• Put a cloth under the box and pull it using the cloth.

• Create a pattern on the surface of the box.

• Ensure the surface of the box is clean.

Tags

NGSS.MS-ETS1-2

Ways to reduce frictional force

• use lubricants

• use grease

• use magnesium carbonate chalk powder

• use rollers and ball bearings

If the type of surface is smoother, the distance traveled by the toy car will be___________________

Tags

NGSS.3-PS2-1

NGSS.3-PS2-2

The frictional force_________________ caused the boy to fall.

The use of lubricants in motor vehicles ______________

the excessive frictional force in the engine

compartment.

• reduces

• increases

• reuses

• enlarge