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How can a humidifier make a cloud without boiling water?

The visible cloud from an ultrasonic humidifier is made of tiny liquid droplets. A vibrating element can produce that mist without boiling the water. Evaporation is a different change: liquid becomes invisible water vapor. Comparing an ultrasonic device with an evaporative humidifier separates the appearance of a cloud from the physical process that adds moisture to air.

3–7 min

Questions you could explore

  • Where in this sequence does liquid become gas, and where does it merely become smaller droplets?

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Engineering and inventions

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How GPS finds you, and fixes its clock

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8–10 min

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Engineering and inventions

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Changing bicycle gears changes the relationship between your pedals and the rear wheel. The teeth on the chainring and sprocket help explain why the same turn of the pedals can produce a different distance along the road.

3–5 min

Why does one pedal turn take you different distances?

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How can a humidifier make a cloud without boiling water? | Speech Topic | speaking.app