Syringe Activity- How does air move? Push & pull the plunger and make observations about how pressure feels and how air moves 1) With the Tube open 2) With the tube clamped shut Is it harder to push the plunger in and pull it out with the tube open or clamped off? What is causing it to be more difficult?

Model of Air molecules http://www.youtube.com/watch?v=08ezkSrQ5lc&feature=related Make diagrams of push and pull

Syringe Activity- How does air move? With the tube clamped shut, push on the plunger then release the clamp. -Which way does the air move? Why? Put the clip back on, pull on the plunger then release the clamp. 3) Draw diagrams.

Cause of Air Movement Need to think about air pressure in one place compared to it’s surroundings Ex) Sisters – 1 person alone is not cause, it’s relationship between both of them Can make comparisons- 1 is older than other High pressure moves to low pressure

Cover the cup with an index card. Invert the cup. What happened? PRESSURE CIRCUS Activity 1. Inverted Cup Challenge: Results and Explanation: Fill a cup with water. Cover the cup with an index card. Invert the cup. What happened? Does the water spill out of the cup? Explain (using concepts on pressure) Summary:

Inverted Cup Why is it low air pressure inside the cup? When cup is completely filled with water, no air is left in cup, thus no air pressure. cardboard High Air Pressure Pressure is in all directions. High pressure outside pushes towards low pressure inside and holds card in place Air pressure can be stronger than water pressure

The picture below is a “before and after” shot of a Styrofoam cup that was brought to a depth of 1770 ft. in the waters off the Gulf of Mexico on September 28, 1994. P = 5,500,000 Pa What do you notice about the cup that was brought underwater? What might have caused the changes that you notice? Does this suggest that water pressure behaves in one direction or all directions? Do you think that water pressure is similar to air pressure? Why or why not?

How can cause a can to collapse? Title: Activity 2. Collapsing Can Date: Feb. 2010 Challenge: Solution: Results and Explanation: How can cause a can to collapse? Explain the principle behind the collapsing can. Summary:

Collapsing 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. http://www.youtube.com/watch?v=p3b9pK-O6cE&list=UUHnyfMqiRRG1u-2MsSQLbXA&index=22&feature=plcp

Collapsing Can Pressure is in all directions. http://www.youtube.com/watch?v=p3b9pK-O6cE&list=UUHnyfMqiRRG1u-2MsSQLbXA&index=22&feature=plcp Collapsing Can - the can was filled with water and air. -boiling the water steam pushed the air out of the can (LESS AIR PARTICLES). - turn can upside down to block the hole in can air can’t go in or out  Lower pressure inside so higher pressure outside push on the can and crush it. Pressure is in all directions. High pressure outside pushes towards low pressure inside and caused can to collapse Air pressure can be strong enough to crush metal

Who was successful and who wasn’t? Title: Activity 3: Straw drinking race Date: Feb. 2010 Challenge: Results and Explanation: Who can drink the fastest? Regular straw Modified straw Who was successful and who wasn’t? Explain how a straw works for 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?) Why was the person unsuccessful? Summary:

Straw Drinking Race 1) Sucking creates a partial vacuum or a lower pressure in straw above the liquid that we drink 2) The higher pressure in outside air pushes the liquid up the straw in our mouth The student with the modified straw cannot create a good vacuum (low pressure/no air) for very long BECAUSE air from higher pressure outside comes in through the holes instead of pushing liquid up the straw

DID NOT DO THIS ONE How can you stop the leak in this soda can? Title: Activity 4 Stop the Leak Date: Feb. 2010 Challenge: Solution: Results and Explanation: How can you stop the leak in this soda can? DID NOT DO THIS ONE Summary:

Air pressure outside of can is greater than air pressure inside. Stop the Leak By 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 out Air pressure outside of can is greater than air pressure inside.