Crushing Cold

Use warm water to rinse out a plastic jug. While the air in the jug is still warm, put the cap on tightly and place the jug into a freezer for two or three minutes. The jug should now be partially crushed.

What crushed the jug?

Explanation

Air pressure crushed the jug. Air is made of tiny bits called molecules. When the air inside the bottle was warm, the molecules bounced around fast, pushing outward against the sides of the jug. When the air cooled in the freezer, the molecules slowed down. They did not push outward as hard as before. Then the pressure of the outside air squeezed the jug, crushing it.

Source: highlightskids.com

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