Ice water beats freezer air

An ice-water bath chills a can 5–10× faster than freezer air.

Why it works

Water conducts heat away far better than air — convective transfer is an order of magnitude stronger. Add salt and stir to go faster still.

Do it exactly

Estimate with the rule, then check it against the calculator that models it properly.

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More in Physics Simulation

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• A metre swings in two secondsA 1 m pendulum takes almost exactly 2 s per full swing.
• Pendulum period: √length, not massQuadruple a pendulum’s length and it swings half as fast. Mass doesn’t matter at all.
• Falling: 5 metres in the first secondA dropped object falls ~5 m in the first second and gains ~10 m/s of speed every second.

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