If gravity keeps humans down, how come it doesnt hold air down?

Question

My science teacher has no idea.

Answer 1

It does. Water is held down too and if you were in it, it would seem the same.

Answer 2

Gravity does hold the air down. If you see Discovery Channel shows about people going up HUGE mountains and that they need air tanks cause of the thin air it should shed a bit more light on the subject with your teacher. As well as Jets if not pressured correctly it would be hard to breath in the jets. There are tons of ways that you yourself have seen what gravity can do and air has boundaries just the same as everything else.

Answer 3

Your science teacher is a ******* retard.

There are some special cases, though. For example: the reason the entire atmosphere isn't crushed into a one inch thick layer is the collisions between gas molecules cause enough pressure to keep the atmosphere spread out. Furthermore, hydrogen and helium are both light enough that these collisions often give individual molecules or atoms escape velocity, and over time those gases escape from the gravity of a planet such as Earth. Almost all gases are light enough for this to happen on planets such as Mars or Mercury, and both of those planets have extremely thin atmospheres as a result. Smaller objects such as the moon don't have any atmosphere because any nearby gas molucules routinely acheive escape velocity.

Answer 4

It does hold air down. Your science teacher should not be teaching science. If it didn't hold air down it would all be floating in space. However, the internal energy of the air molecules keeps them bouncing around so that it doesn't just lay flat on the ground in a thin layer. But it's more dense near the ground and less up away from the earth.

Answer 5

Talk about a crisis in science education. Yeesh.

Gravity DOES hold the air down. Atmospheric pressure is caused by the weight of the air above you. It's exactly analogous to water. The pressure increases the further you go down.

Answer 6

Gravity holds air down. If your teacher doesn't know what causes atmospheric (barometric) pressure, tell him:
1 - Atmospheric pressure is caused by the effect of gravity on air.
2 - The website under Source(s) below will tell your teacher that atmospheric pressure is due to the weight of air.
3 - Your teacher should know that weight is the product of mass times acceleration due to gravity. So the weight of air that causes atmospheric pressure is itself partly causes by gravity.

Answer 7

Gravity creates an air pressure of about 14.7 pounds per square inch at sea level. This is the weight of a column of air one square inch in area extending from sea level to the top of the atmosphere.

You should try to get another "science teacher" who has a clue.

Answer 8

It does. Compare the atmosphere on the Earth with that on the Moon. Less gravity on the Moon, so less atmosphere. Gravity holds down everything including people, animals, plants, atmosphere, water, etc.

Answer 9

It does.

Without gravity all the air would drift off into space. Your science teacher is brain-dead.

Answer 10

It does, of course. That's what holds the atmosphere on the earth. Either your science teacher is smoked out, or you didn't communicate very clearly.

Answer 11

Gravity does hold air down - otherwise our atmosphere would disappear.