Mysterious Money

What is this Science Bite about?

Make a coin disappear! Learn the science of light behind this great magic trick - amaze your friends!

Always remember to ask your parent or guardian to help you.

You will need

A piece of white paper, glass of water, small saucer and a coin.

  • A piece of plain white paper (or a white tablecloth)
  • A glass of water
  • A small plate or saucer
  • A coin

How to do this experiment

  1. Place your coin onto your piece of paper or white tablecloth.
    A piece of paper with a coin and glass of water on top.

  2. Place your glass on top of the coin then show your audience how your coin can still be seen, by looking through the glass from above.
    Looking down onto the glass of water, with the coin and paper underneath

  3. Carefully balance the plate on top.
    A plate balanced on the glass of water

  4. Watch your audience gasp at how the coin vanishes before their eyes.
    A close up of the glass shows that the coin has mysteriously disappeared
    Stand back and enjoy the applause!

How does it work?

We need light to see and we see objects because light reflects off of them and into our eyes.

Light normally travels in straight lines but if it goes through a see through material like glass at an angle it will bend. This bending is called Refraction and the bending is greater the bigger the difference in density between the two materials

The light reflecting off the coin needs to pass through three different substances; water, glass and air before it gets to our eyes. This has caused the light to bend many times and so the image of the coin does not get reflected into our eyes. It looks as though it has vanished because our brain thinks the light has travelled straight.

Curriculum Links

Vibrations and Waves

SCN 3-11a


Glasgow Science Centre