Defog your windows TWICE as fast using SCIENCE- 4 easy steps
From Mark Rober
5 min4th5th6thScience
Summary
Mark explains the science of why car windows fog up and shares four steps to clear them fast. A short, practical lesson about water vapor and condensation.
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Ages 7+
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Teaching resources
Discussion questions
Talk about it
Warm, moist air meets a cold window and the water vapor condenses into tiny droplets — fog. Changing the air's moisture and temperature clears it.
- Why do windows fog up on cold or humid days?
- What is condensation, and where else do you see it?
- Which of Mark's steps do you think helps the most, and why?
Quick work-a-long
Vocabulary: water vapor, condensation, humidity, temperature.
Try it: Breathe on a cold mirror or window and watch it fog. Explain where the tiny droplets came from.