KS3 Friction, elasticity and pressure

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

• similar
• opposite
• parallel
• west

Tags

NGSS.HS-PS2-1

A type of friction that occurs when air pushes against a moving object causing it to negatively accelerate

• surface area
• air resistance
• descent velocity
• gravity 

Tags

NGSS.MS-PS2-2

How does friction affect speed?

• more friction decreases speed
• more friction increases speed
• less friction decreases speed

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

How can friction be reduced?

• reduce the force acting between the 2 surfaces
• reduce the roughness of the 2 surfaces coming in contact
• use wax, grease or oil
• all of the above are ways of reducing friction

The rougher the surface, the faster an object will travel over the surface.

• True
• False

When two surfaces rub, the irregularities of one surface get caught on those of the other surface?

• True
• False

If extension = Stretched length - original length. What is the extension of spring D.

• 1mm
• 2mm
• 3mm
• 0mm

Where would you find the largest pressure?

• At the bottom of the ocean
• At the top of Mt Everest
• Close to ground on the Scotch oval
• In a rockpool on the Great Barrier Reef

If the pressure in a balloon remains constant what happens to the balloon's volume as the temperature of the air increases?

• the balloon shrivels up
• balloon expands
• balloon stays the same size
• balloon shrinks