1. What Do These Things Have In Common?
These objects need air pressure to work!

2. What is Air Pressure?
What is your guess?

3. Air Pressure… pushes on everything it touches! is all around you!
BUT……
I don’t see it!
I don’t feel it!

4. Air Pressure Pushes Down on Pig Pen!

5. We Can Watch Air Pressure Work!
Watch This!!

6. What Just Happened? What pushed the egg into the jar?
How strong is air pressure?
Why don’t we get squashed
by air pressure?
Have students breath in and out. Ask them, “What do you have inside of you?”

7. Here is what happened… 1. The matches warm the air in
the bottle. When air is heated,
it takes up more space, and it pushes
against the sides of the bottle.
2. Some of the warm air tries to escape
out of the bottle.
3. And when the matches go out, the air in the
bottle becomes cooler.
4. The cooler air takes up less space.
5. Now, the air outside the bottle pushes with
greater power than the air inside the bottle.
6. The greater pressure outside
pushes the egg into the bottle!

10. Air Pressure Doesn’t Squash You Because…
You have air inside of you. It pushes out with the same amount of pressure that the outside air pushes in on you.

11. Another reason air pressure doesn’t squash you is because…
Air pushes in all directions!!
Let’s try an experiment!

12. Sometimes You Can Feel Air Pressure Change!
Have your ears ever popped when you’ve gone up a mountain or up in an airplane?
Do you know why?

13. Air Pressure Changes The higher you go, the less air pressure pushes.
Your ears pop
because they
are trying to
make the inside
and outside
pressure equal.
Up here I have little weight on me. I feel little pressure.
Down here I have lots of weight on me. I feel high pressure.

15. So…as you go up, the air in your ears pushes out.
Oww,
my ears!!

16. Calvin & Hobbes are climbing to the top of a mountain
Calvin & Hobbes are climbing to the top of a mountain. Will the air push against them more or less when they reach the top? Explain your answer.

17. Answer: Less The higher they go, the less air there is to push on them.

18. This is what you do…
With your partner, make up a song about air pressure.
Write down the words on a piece of paper.
Sing your song for another group.
If you want, you can sing it for the class.

19. Find out how air pressure can make the weather be sunny or rainy!
…to be continued
Find out how air pressure can make the weather be sunny or rainy!
What’s your guess??!!