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Time Dilation & Length Contraction

Try this: Find the speed at which the ship's clock ticks half as fast.

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About this simulation

One light clock, two frames, and the geometry that makes both observers right.

Taught in Special Relativity

  • time dilation
  • length contraction
  • invariance of c
  • simultaneity

How this runs

The equations of motion are integrated in your browser at a fixed timestep, so the numbers do not depend on your screen’s refresh rate. Nothing is sent to a server. Use Share setup to copy a link that reproduces exactly what you are looking at.