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Brainteasers

How tall must a mirror be to show your whole body?

geometryreflectionopticsclassic

You stand in front of a flat, vertical mirror mounted on a wall and want to see your entire body, from the top of your head to your toes, at the same time.

  1. What is the shortest mirror that lets you do this?
  2. Does it help to stand further away from the mirror?
  3. Where on the wall should the mirror be mounted?
Show a hint

Light from your toes reaches your eyes after bouncing off the mirror at a point where the angle in equals the angle out. Where is that point?

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