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Married people live longer in Swiss statistics, but marriage is no personal longevity guarantee. Check the population and distinguish association from cause.

See light refraction with a spoon in a glass of water. Shift your viewing angle to reveal why a straight handle can look bent at the waterline.

Why metal feels colder than wood is easy to test with two spoons. Your skin responds to how quickly it loses heat, not just the object's temperature.

Reduce microfibers in laundry: wash synthetics only when needed, choose a suitable gentle cycle and check whether a fiber filter fits your machine.

Compare salt and ice with an unsalted portion using two thermometers. Watch how melting can cool the salty mixture below 0 °C instead of warming it.

Moon phases are not caused by Earth's shadow. Use a ball and an LED lamp to see why the same sunlit half can look like a crescent or a full Moon.

A one-leg stand need not be hands-free: use a sturdy wall and practise for 5–10 seconds per side, only while you feel steady and in control.