# Bending Light

## Objective

To observe behavior of light under different conditions.

Procedure: Easy

Concept: Easy

## Concept

Even though we interact with light every day, it has mysterious characteristics. One of these characteristics is how light interacts with other materials in the world.

Light is thought to be both a wave and particle. The waves are known as electro-magnetic waves and the particles are known as photon. By seeing how light interacts with materials, can you give information about the materials? In order to do so, we need to understand how light interacts.

One of the most prominent interactions we observe is bending of light. It can be easily observed when you are at the aquarium. There is a law called Snell's Law that explains how much light bends.

Snell's Law describes the behavior of light in terms of a parameter called the index of refraction (n). The index of refraction varies from material to material.

Thanks to commercially available lasers, we can observe this easily by putting graph paper behind glass!

## Personalizing Your Project

• How does light bend in sugar water? How about salt water? How about different concentrations? What does that tell about the light interaction with sugar or salt water?
• How does light bend if there is current flow in the water? Does it change as the direction of current changes?
• How do different colors of light interact differently?
• How does index of refraction change from material to material? (Advanced)
• What is the relationship between the index of refraction and speed of light?
• What other effects does material have on the light? Does it change its speed? Color?

## Things to Consider

• Do not point lasers directly in the eyes.
• If conducting current, make sure no one can get shocked

## Google Key Words

To do more research on the bending of light, try typing these words into a Google search.

• Snell's Law
• Electromagnetic Wave
• Speed of Light
• Permittivity
• Optics
• Ray Tracing
• Index of Refraction
• Fermat's Principle