5.3 Friction, air resistance, water resistance and upthrust

Friction always acts:

• weight

• air resistance

• upthrust

Friction always acts:

• In the direction of motion

• Opposite to the direction of motion

• randomly

Which factor affects the magnitude of friction?

• surface roughness

• object size

• surface temperature

Air resistance affects objects moving through .....

........................ shapes help reduce water resistance.

What type of force opposes motion in fluids like air and water?

• drag

• friction

• upthrust

What happens when an object experiences high water resistance?

• It accelerates.

• Its speed decreases.

• Its weight increases

The force that makes it difficult to move through water is called ..........

Upthrust is always directed upwards.

• True

• False

Which of the following does not experience upthrust?

• A wooden log floating on water

• A hot air balloon

• A stone lying on dry land