Report Copyright Infringement View in OSM UK

Description

A glass full of water will reverse the image placed behind it

Resources

Straight glass
Images to place behind - e.g. double set of arrows pointing in the same direction, People holding item in one hand, "now"

Instructions

Place cards with pictures or words on a certain distance behind the glass and see how the images the image is, then fill up the glass so that the bottom arrow is covered. The arrow changes direction. Then fill it up further and both arrows change direction.

Explanation:
Refraction, the bending of light.

When the arrow is moved to a particular distance behind the glass, it looks like it reversed itself. When light passes from one material to another, it can bend or refract. In the experiment that you just completed, light traveled from the air, through the glass, through the water, through the back of the glass, and then back through the air, before hitting the arrow. Anytime that light passes from one medium, or material, into another, it refracts.

Just because light bends when it travels through different materials, doesn't explain why the arrow reverses itself. To explain this, you must think about the glass of water as if it is a magnifying glass. When light goes through a magnifying glass the light bends toward the center. Where the light all comes together is called the focal point, but beyond the focal point the image appears to reverse because the light rays that were bent pass each other and the light that was on the right side is now on the left and the left on the right, which makes the arrow appear to be reversed. Diagram explaining it attached

Tags

• optical illusions
• Refraction
• reversing image

Badge Links

• Experiment - Experiment