Speed of Light

In this lab we will study the speed of light.

Background

As a little bit of background research, you might consider saying a little bit about why it was important to measure the speed of light, who it was who first did so, and how.

Laser Safety

The U.S. Dept. of Health, Education and Welfare regulates laser manufacturers to see that users are not endangered. The federal government classifies lasers according to their power levels and specifies appropriate safety features for each level.

Take the following steps to ensure that optimum safety is achieved when the laser is being used.

  1. Do not look into the beam or stare at its bright reflections.
  2. Block off the beam at a point beyond the farthest point of interest. Use a dull, non-reflective object, such as a piece of wood.
  3. If the beam is to travel a long distance, keep it close to the ground or overhead so that it does not cross a walkway at eye level.

Experiments

In this lab, I would like you to really be an experimentalist. I am going to give you a basic idea of what you need to do, but then leave you to work out details. You will need to experiment, ask questions, and then refine - you should expect to redo experiments and try to determine what problems are if you run into any or if results do not work out.

Exercise 1: How can you determine whether a light source is a laser? What specific properties would you measure and how would you measure them to determine if a light source is a laser.

You should measure the speed of light in two ways:

Other Uses for a Laser