Atmospheric Pressure

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PowerPoint Handouts for Atmospheric Pressure

AtmosphericPressure

Review: Pressure is the force exerted on the body per unit area.

Atmospheric Pressure - isthe force exerted on you by the weight of tiny particlesof air.

•Air pressure in the atmosphere tends to drive gases to fill up space where there is absence of gaslike in vacuum.

What Happensif Air Pressure Changes?

Haveyou been at the top of the mountain?Why do your earspop?

If you've ever been to the top of a tall mountain, you may have noticed that your ears pop and you need to breathe more often than when you're at sea level.

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And so:

As the number of molecules of air around you decreases, the air pressure decreases.

This causes your ears to pop in order to balance the pressure between the outside and inside of your ear.

Since you are breathing fewer molecules of oxygen, you need to breathe faster to bring the few molecules there are into your lungs to make up for the deficit.

At higher altitude, air pressure decreasesbecause the amount of air islesser.

Consequently,

At sea level the air pressureincreases.