What is Light?

The only thing we really see is light. But what is light? Light has been studied for thousands of years. Some of the ancient Greek philosophers thought light consisted of tiny particles, which could enter the eye to create the sensation of vision. Others, including Socrates and Plato, thought that vision resulted from streamers or filaments emitted by the eye making contact with an object. This view was supported by Euclid, when he asked how else we can explain why we do not see a needle on the floor until our eyes fall upon it.

Up until the time of Newton and beyond, most philosophers and scientists thought that light consisted of particles. However, one Greek, Empedocles, taught that light traveled in waves. One of Newton’s contemporaries, the Dutch scientist Christian Huygens, also argued that light was a wave. Much evidence has been collected over the years to support both theories of the nature of light.

Task…..

• You will compile a list of evidence that shows how light behaves and/or  explains the nature of light.
• You will categorize the pieces of evidence into two separate lists as to  whether it supports the theory of light acting as a particle or acting as a wave.
• You will construct diagrams for each of the two theories to illustrate at least one piece of evidence from your lists that supports that theory.

Assessment…..

You will be assessed on:

• Your content understanding of the nature of light, including but not limited to, ample knowledge of the behaviors of light and how they can be credited to either the wave explanation or the particle interpretation, or both.

{H1} Analyze the evidence that leads scientists to conclude that light behaves somewhat like a wave and somewhat like a particle.

• Your ability to recognize and analyze a situation where there is more than one explanation for a phenomena.

{K6} Analyze situations where more than one logical conclusion can be drawn.

• Your ability to represent a concept with a diagram, model, picture , etc. to create a visual and help simplify the idea and solve a problem.

{L3} Make and use appropriate symbols, pictures, diagrams, scale drawings, and models to represent and simplify real-life situations and solve problems.

Refer to the rubric attached to develop your report.

Sources for this Project:

Web sites on the Physics page - many good portals to search

Bibliography of sources in the CHS Library.