Let's learn how to make a working lung!
You will need:
- 2 balloons
- Empty bottle and cap
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Straw
-
Scissors
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Box cutter
-
Screwdriver
-
Blu-tack
-
Tape
-
An adult to help
Photo: Handout
Directions:
Step 1: Using a cutter, ask an adult to help you cut off the bottom of the bottle.
How it works
When the bottle is sealed by the balloon on one end, and the cap, straw and balloon at the other end, it is nearly airtight. This means air cannot go in or out.
When you pull the balloon, the volume of the container increases. However, the volume of air inside the container stays the same. This makes an area of low air pressure inside the bottle, while the air pressure outside the bottle stays the same. The higher air pressure from outside the bottle forces itself into the straw. Outside air rushes in to fill the straw and the balloon until the air pressure has balanced out.
Releasing the balloon brings the container back to its original air pressure, and the balloon deflates as air goes out of the straw.
