1.  Place the blu tack in the middle of the coin.

2.  Position the blu tacked coin in the center of your pot so that it is secured down (will not move when you pour water into the pot).  Pour some water into your glass.

3.  Move backwards away from the bowl until you cannot see the coin in the bowl.

4.  Very slowly pour some water into the bowl until the coin starts to appear before your eyes.

5.  Pour a bit more water, very slowly, and continue watching as the coin reveals itself.  Watch the bowl from where you are standing.

   

Materials                               Step 1

 

Step 2                                   Step 3

 

Step 5                                   Step 6

What do you see?  

When the bowl is empty the edge of the bowl stops you seeing the coin.  

When the bowl is full of water the light bends over the edge so you can see the coin.  

Have you ever noticed that things at the bottom of a pool or river always look closer to the surface than they really are?  

This is due to the way light bends through water and is an effect of refracted light.