Formation of Images
Light, Sound and Waves

Mirror Mirror

Enrichment Activity for 5-11 11-14

What you need

  • A small mirror
  • A blank wall
  • A friend

Instructions

  1. Sit opposite your friend and next to a pale, blank wall. With the wall to your right, hold the mirror in your left hand and put it next to your nose
  2. Angle the mirror so that your right eye sees only a reflection of the wall
  3. With your left eye looking at your friend, wave your right hand so your right eye can see it reflected in the mirror
  4. Watch bits of your friend’s face disappear!
  5. Don’t give up if it doesn’t work straight away – try switching eyes, holding your head very still and making sure your friend doesn’t fidget

Results and Explanation

Each eye is seeing something very different and as your brain tries to make a sensible single image, it combines bits from both eyes. But your brain is sensitive to movement so it focuses on your moving hand and your friend disappears.

These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.

Formation of Images
can be represented by Ray Diagrams
is used in analyses relating to Lens
has the special case Real Image Virtual Image
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