Presentation on theme: "Air Pressure Lightbulb Lab. Air Pressure Without air we could not live. We cannot see it or smell it, but we can feel it when it moves. Just like water,"— Presentation transcript:
Air Pressure Without air we could not live. We cannot see it or smell it, but we can feel it when it moves. Just like water, air has many uses. Sailing boats have large sails which catch the wind to push them through the water. Windmills harness the power of the wind to grind wheat into flour or make electricity.
Air Pressure Did you know that air pushed against you all the time? You cannot feel air pushing in on you because your body pushes outwards with the same force as the air. In outer space, where there is no air, astronauts have to wear pressurized space suits that push against their bodies with the same forces as the air on earth.
Candle in the Wind Materials you will need: A Lighter or Matches Tea-Light Candle (Small) Tall Round Container (Salt Container) This is amazing! Steps: 1. Place the candle just behind the round container. 2. Light the candle. 3. Blow against the round container from the front and at candlelight level. What did you think would happen? This works the same with liquids. The fluid or air tends to flow (follow) the contour of the round container. When the flow of air meets on the other side of the container, they join together to blow out the candle.
Killer Straw Materials you will need: Raw Potato Plastic Drinking Straws Steps: 1. Place the potato on a table top. 2. Hold the straw at the top (without covering the hole). 3. Try to stab the straw into the potato. 4. Next, hold your thumb over the hole in the top of another straw. 5. Try to stab this straw into the potato. What happened? 1.) The open-ended straw bends and only a little bit of the straw penetrates the potato. 2.) The closed straw (with your thumb covering the top of the straw) cuts deeply into the potato. The air trapped inside the straw gives the straw enough strength to penetrate the skin of the potato. As the straw enters the potato, the potato plug compresses the air inside the straw, increasing the air pressure, and strengthening the straw.
Lift a Friend Materials you will need: A friend Large, heavy book A table top or counter top Thick plastic shopping bag (with no holes) A pair of healthy lungs This is an amazing experiment! Can you lift a friend off a table top without touching your friend? Steps: 1. Lay a strong plastic shopping bag on a table top or counter top so its top third hangs over the edge. 2. Place the large book on top of the bag and ask your friend to sit on top of the book. 3. Gather the open end of the shopping bag into the shape of a balloon opening (mouth piece). 4. Blow into the bag hard to fill it with air to make a balloon. Keep blowing to force the air into the bag so that it inflates and pushes or lifts your friend off the book. This is the pushing power of air. It works because air from your lungs is spread over a wide area, so it can support a lot of weight.
Amazing Paper Ball Materials you will need: A piece of paper A plastic drinking bottle (any size) Steps: Use a clean and dry recycled plastic drinks bottle, one that is easy to hold with one hand. 1. Roll up a bit of paper into a small ball that will fit easily into the opening of the drinks bottle. 2. Hold the plastic bottle so that it is horizontal and rest the ball of paper just inside the neck/opening of the plastic bottle. 3. Hold the bottle with the ball up close to your mouth and blow into the opening. 4. Go on; try it again and again and again. What happens each time? Have a go at trying this experiment with different sized (openings) drinks bottles and different types of paper (tissue, tin foil, tracing paper) The air that you blew into the bottle hits the back or bottom of the bottle and bounces back out the opening of the bottle and forces the paper ball to blow out.
Sucked In Materials you will need: A Hard Boiled Egg A Clear Glass Jar (with a small mouth) Paper Towel Matches This is an incredible experiment to watch! Is it possible for an egg to be sucked into a jar opening that is smaller than the egg itself? Watch and be amazed! Steps: 1.Crack and peel the hard boiled egg. 2.Roll the paper towel to make a wick. 3.Light the paper towel and quickly drop it into the glass jar. 4. Place the hard boiled egg on the top (mouth) of the jar. 4.Watch and wait to see what happens. An egg is not a solid; it has air pockets like a sponge. By burning the air in the jar you decrease the pressure inside the jar which causes the egg to decrease in size, becoming a solid and allows the egg to slip through the opening of the jar.