air pressure activities

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Air Pressure Activities A.Inverted Glass B.Stop the Leak C.Collapsing Can D.Fastest Drinker In your notebook: 1.Diagram of set-up 2.Description of results 3.Explanation/ principle involved

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Air Pressure Activities. Inverted Glass Stop the Leak Collapsing Can Fastest Drinker. In your notebook: Diagram of set-up Description of results Explanation/principle involved. Air Pressure. Air Pressure. - PowerPoint PPT Presentation

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Page 1: Air Pressure Activities

Air Pressure Activities

A.Inverted Glass

B.Stop the Leak

C.Collapsing Can

D.Fastest Drinker

In your notebook:

1. Diagram of set-up

2. Description of results

3. Explanation/principle involved

Page 2: Air Pressure Activities

Air Pressure

Page 3: Air Pressure Activities

Air Pressure• Air Pressure is

a measure of the force of the air pressing down on the earth’s surface

Page 4: Air Pressure Activities

Air Pressure can vary at any can vary at any particular point on the Earth particular point on the Earth

depending on the density of the airdepending on the density of the air

Density = mass / volumeDensity = mass / volume

Page 6: Air Pressure Activities

Inverted CupInverted Cupcardboard

Air Pressure

When cup is completely filled with water, no air is

left in cup, thus no air pressure. The inverted cup can therefore hold

water up because the air pressure is working

against the underside of the cup.

There is higher air pressure outside pushing There is higher air pressure outside pushing upward than the inside of cup pushing downward.upward than the inside of cup pushing downward.

Page 8: Air Pressure Activities

Stop the LeakStop the LeakBy plugging one of the holes, the air inside stays the same because

outside air is prevented from coming into the hole. The higher

water volume inside causes a decrease in pressure. Thus, outside air pressure (which is

greater) pushes against the water and prevents it from flowing out.

Air cannot go in

Liquid cannot

flow outAir pressure outside of can is Air pressure outside of can is

greater than air pressure inside.greater than air pressure inside.

Page 9: Air Pressure Activities

Challenge:

Solution:

Results and Explanation:

How can cause a can to collapse?

Title: Activity 3. Collapsing Can Date: Feb. 2010

Summary:

Explain the principle behind the collapsing can.

Page 10: Air Pressure Activities

Collapsing CanCollapsing Can

Before heating, the can was filled with water and air.

By boiling the water, the liquid changed into water vapor

The water vapor or steam pushed the air that was inside, out of the can.

In closing off the can, air is prevented from going back to the can.

Cooling (water in basin) condenses water vapor back to water. All the

vapor which took up space inside the can turned into a few drops of

water, which take up less space.

Pressure inside can drops allowing outside air pressure to push on the can and

crush it.

Page 11: Air Pressure Activities

Challenge:

Results and Explanation:

Who can drink the fastest?

Title: Activity 3. Straw drinking race Date: Feb. 2010

Summary:

Explain the principle behind straw drinking. When you drink liquid through a straw, is it accurate to say the liquid is sucked up the straw or pushed up the straw?

Regular straw Modified straw

Page 12: Air Pressure Activities

Straw Drinking RaceStraw Drinking Race

Sucking creates a partial vacuum or a lower pressurelower pressure in straw above the

liquid that we drink

The higher pressure in outside air pushes the

liquid up the straw in our mouth

The student with the leaky straw cannot

create a vacuum above the liquid, so the liquid

is not pushed up.

Page 13: Air Pressure Activities

DensityDensity = Mass / Volume Warm air is less dense than cool air. Warm air rises. Cool air sinks.

Air at high altitudes is less dense than air at lower altitudes.

Page 14: Air Pressure Activities

Factors that affect Factors that affect Air Air PressurePressure

TemperatureTemperature

Water Vapor

Elevation

Page 15: Air Pressure Activities

TEMPERATURE AND AIR PRESSURE

HEAT

Molecules move faster

Move apart, become fewer and weigh less

LESS AIR PRESSURE

Page 16: Air Pressure Activities

HIGH TEMPERATURE, LOW AIR PRESSURE

LOW TEMPERATURE, HIGH AIR PRESSURE

Page 17: Air Pressure Activities

AMOUNT OF WATER VAPOR

consists of air and water molecules

Page 18: Air Pressure Activities

More water vapor means less air

moleculesLOW AIR PRESSURE

DRY AIR = HIGH AIR PRESSURE

Page 19: Air Pressure Activities

Factors Affecting Air PressureFactors Affecting Air PressureFACTOR Increase/Decrease Air Pressure

DensityDensityTemperatureTemperatureWater VaporWater VaporAltitude Altitude

Page 20: Air Pressure Activities

Measuring Measuring Air PressureAir Pressure

Air Pressure is measured by an instrument called Barometer

Types of BarometerMercury BarometerAneroid

Page 21: Air Pressure Activities

Air pressure increases, column of mercury rises

Air pressure decreases, column of mercury drops

Page 22: Air Pressure Activities

Air PressureAir Pressure & & WeatherWeather

Page 23: Air Pressure Activities

High pressure generally means fair weather

Air mass in upper atmosphere

Layer of Air

Warm, moist air cannot rise

No clouds

Page 24: Air Pressure Activities

Low pressure generally means cloudy, rainy weather

Air masses move apart

Warm air rises, clouds form

Page 25: Air Pressure Activities

QUESTIONS – use your QUESTIONS – use your knowledge of air pressure to knowledge of air pressure to

explain the following situationsexplain the following situations A falling barometer is followed by A falling barometer is followed by

several days of rainy weather.several days of rainy weather. Some people find it hard to Some people find it hard to

breathe at high altitudes.breathe at high altitudes. A rising barometer indicates a A rising barometer indicates a

spell of cool dry weather.spell of cool dry weather.