How to Bend Light by Refraction

Light is bent as it passes through water. This bending is called refraction. It can make objects look odd when viewed through water. In order to see refraction in action, conduct this simple experiment that requires only household items.

Things You'll Need

• Glass
• Water
• Pencil

Instructions

1. Fill a glass about two-thirds of the way with water. Leave at least a few inches at the top of the glass empty so that you will be able to observe the results of the experiment.

2. Insert a pencil into the glass of water. First, hold it straight up. Look at the pencil from the side, and notice that there is a discrepancy between the way that the pencil's placement looks when it's in the water as opposed to the way its position looks above the water.

3. Lean the pencil against the side of the glass. Notice that there is a difference in the discrepancy. The placement discrepancy still exists, but it will seem a little different that it did when the pencil was straight up and down in the water. This is the effect of refraction on the way that the pencil looks.

4. Move the pencil so that it is in the water at different angles. You can see that refraction affects the way that the pencil looks in different ways depending on the angle.

5. Move your own position so that you can see the pencil from different angles. Leave the pencil stable, and just view the difference in its appearance as you move your position rather than the pencil's.

Tips & Warnings

• Conduct the experiment in a well-lit room so that you can see the results well.

• Use a pencil that you don't need. Water could ruin it.