Quantum & RelativityRelativity

The Universe's Speed Limit

Nothing can outrun light, and that changes time itself

Throw a ball from a moving car and it flies faster. Shine a flashlight from that car: does the light go faster too?

You'll find out

  • Why light ignores your speed
  • What a moving clock does
  • Why no train reaches light speed

Why it matters

Speed changes how fast time passes. It's tiny in daily life, but your phone has to deal with it.

About 3 min6 interactive slides · 5 questionsLesson 186 · Zone 21

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