1. If you let go of a ball, what will it do?

Remain at the spot where you let go

Fly upward

Fall to the ground

Change colors

2. What force causes a ball to fall to the ground?

Lift

Gravity

Magnetism

Van der Walls

3. Why do your ears "pop" when you drive up a mountain?

The air pressure changes

So that you know when to yawn

So that you know how high up you are

So that you know to breathe faster

4. An airplane can fly because ________.

air moves faster over the top of the wings than the bottom

a force called "lift" pushes the plane upward

air pressure is greater under the wings than on top of the wings

all of the above

5. Which statement does Bernoulli's principle apply to?

Energy can neither be created nor destroyed.

A bird in hand is worth two in the bush.

Air that moves quickly has less pressure than air that moves slowly.

E = m c^2