Chapter 11.7, Problem 2eT

An observer is looking at a light source through two polarizers as shown in the side view diagram at right. The polarizers are crossed, that is, they are oriented so that the light transmitted through them has minimum intensity.

1. Suppose that a third polarizer were inserted a, the position marked X, shown above.

Predict how, if at all, this change would affect the, intensity of the light reaching the observer. Does your answer depend on the orientation of the third polarizer? Discuss your reasoning with your partners.

Check your prediction experimentally. (Ask a tutorial instructor to show you the equipment that you need in order to do so.) If your prediction was incorrect, identify those parts of your prediction that were wrong.

How can you apply your results from part D to help you account for your observations? Support your answer with one or more diagrams.

2. Suppose that instead a third polarizer were inserted at the position marked Y, shown above.

Predict how, if at all, this change would affect the intensity of the light reaching the observer. Does your answer depend on the orientation of the third polarizer? Discuss your reasoning with your partners.