EXPANSION OF LIQUIDS
Fit two or three medicine bottles or test tubes with corks and tubes. Fill them with a variety of liquids and immerse them in a pan of hot water. The air rise inside the tubes indicates difference in expansion.
EXPANSION OF GASES
The medicine bottles can also show the expansion of air or other gases. Push the glass tube through the cork and trap some air. A hand placed on the bottle drives liquid up the tube. Warming the bottle causes air to be expelled. This reduces pressure inside. When the bottle cools, liquid is forced up the tube.
Stretch a rubber balloon over the neck of a flask which has been made from a used electric bulb. Heat the flask gently with a small flame and watch the difference.
Partially inflate a balloon and hold it over a hot plate or place it in the warm sun for a while and observe the results.
Have students take a look at the family car with their parent and observe the following:
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a) Tires for air
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b) Start the car and observe the dashboard for lights, and fuel gauge, also take a look at the engine while it is running.
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c) Make notation of their parts and functions based upon information received.
