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Lesson 5 of 14

Light bounces off a smooth surface

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5 min

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A shiny steel plate makes a bright patch on the wall. Tilt the plate, and the patch moves.

A ray comes down and hits the mirror.
Step 1 of 4
  1. A ray comes down and hits the mirror.
  2. It leaves again, on the far side.
  3. The two slants (angles), arriving and leaving, are the same.
  4. Tilt the mirror, and the ray goes somewhere new.

The new word

  • Reflection — light bouncing off a surface.

The rule

Light hits a smooth surface and bounces off. The slant out equals the slant in, measured from the surface. Tilt the surface, and the light goes somewhere new.

Now try it. Tilt the mirror. Which card does the light hit?

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