Angled flat mirrors: Quantitative Testing Experiment

Aim

Test your newly devised rule for reflection of light.

Prior Knowledge

• A rule for reflection

Description of the Experiment

DO NOT play the movie. Look at the first movie frame and you should see the following: Two flat mirrors angled at 90 degrees to each other, and an incoming ray of light from the laser. Your goal is to use your new rule for reflection to predict the subsequent path of the ray.

It might help to use a transparency on the screen and to trace it out. Then run the movie and compare with your prediction.

Youtube movies can be stepped frame by frame using the , and . keys on your keyboard. If you want to download the movie to your computer, right-click or control-click HERE.

Questions

• Decide what physical quantities you need to measure to make a prediction.
• What physics principles do you need to use ot make the prediction?
• Use the measurements and the pricniple to make the prediction. What is the experimental uncertainty in your prediction?
• Run the movie and see whether your prediction is confirmed.
• What is your judgment about the principle under test?