Bathtime Science!

Follow these directions for some fun in the bath. (I don't have to remind you to use a glass made of plastic and not glass, just in case of accidents, do I?)

Push a dry cloth or a piece of tissue to the bottom of a tall glass and put the glass in the water with the open end facing down. Ask your child to look inside and he will see that the glass is still partly empty. When you lift the glass out of the water, the cloth will still be dry!

This happens because of air pressure: as the glass is pushed into the water, the air in the glass has nowhere to go and gets squeezed against the bottom. There's no more room in the glass for the water, and so the cloth stays dry.

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