airpressure presentation4

Download Airpressure presentation4

Post on 06-Aug-2015

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  1. 1. Air Pressure Air Occupies Space Air Exerts Pressure
  2. 2. Experiment #1 Air Occupies Space
  3. 3. Fill a beaker/bowl three quarters full with water.
  4. 4. Place a piece of paper halfway down a test tube/glass.
  5. 5. Push the glass, mouth first, into the water and
  6. 6. Lift it out again.
  7. 7. Remove the paper. Is it wet?
  8. 8. Why? Paper is not wet because air in the glass istaking up the space. Try pushing down on the handle of a bicyclepump while closing the nozzle of the pump with your thumb. Notice what happens .. Discuss your experience with yourclassmates.
  9. 9. Experiment # 2 The Collapsing Can
  10. 10. Add a small amount of water in empty cans and let it boil until all of it evaporates.
  11. 11. Remove the cans from the Bunsen burner/stove and immerse the cans in a bowl of cold water or place them under cold flowing water from the tap. Notice what happens
  12. 12. Both cans collapsed wow
  13. 13. What happened? When the water boils in the cans, it changesinto steam. Steam drives all the air inside, out of thecans. As the can immerses into the cold waterwater, the steam immediately condenses into water. As the air is removed from inside the can,the weight of the air/atmospheric pressure crushes the container.
  14. 14. Experiment # 3 Hard Boiled Egg
  15. 15. Hard boiled egg doesnt go through the narrow mouth of a conical flask/ bottle.
  16. 16. Light a candle inside the bottle and
  17. 17. Put the hard boiled egg on its mouth. Immediately.
  18. 18. Egg goes inside the bottle
  19. 19. What happened? When the candle burns, oxygen is used up. This reduces the amount of air in the bottle,which decreases the air pressure inside the flask. The higher pressure outside the flask thenpushes the egg in.
  20. 20. Produced by Khaula Shehzad Audio by Shorthopper