Tag Archives: straight

Is the pencil magic?

pencil

Light can play tricks on your eyes! Here’s a fast and fun activity that you can do to trick your friends!

bent or straight?

What you’ll need:

- a pencil

- water

- a clear glass jar (like an empty pasta jar)

How to do it:

1) Fill half your glass jar with water

2) Place the pencil in the water

3) Look at the pencil from the top

4) Look at the pencil from the side

When you look at it from the top it looks straight but when you look at it from the side its bent!

Why does it do this?

Its the light playing tricks on your eyes! You see light travels through water slower than it travels through air. When the light hits the water it slows down making the pencil look bent, but when the light travels through air it speeds up making the pencil look straight!