Year 6: Frictional forces and air pressure

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

• mass of the box and roughness between surfaces

• hills and valleys and how smooth or rough the surface is

• Amount of force and amount of surface that the object comes in contact

• The force and the weight exerted on the surfaces

Rougher surfaces have ...

• greater friction

• lesser friction

• the same level of friction

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

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-PS2-1

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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___________________

• increases

• decreases

Tags

NGSS.3-PS2-1

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

• increases

• decreases

The frictional force_________________ caused the boy to fall.

• is increases

• is decreases

A frictional force is the force generated when ...

• no surfaces are in contact

• two surfaces are in contact

• three surfaces are in contact