Equipment per group: an incandescent lightbulb that can be plugged into a socket, and two polarizers. Light is either a transverse wave or a longitudinal wave. Several experiments that test these two hypotheses are described below. The experiments make use of a polarizer, a device made from material that prevents light waves from passing through if something in the wave is vibrating perpendicular to the axis of the polarizer. a. Make predictions, based on each of the two hypotheses, about the brightness of the light once it has passed through the polarizer(s).
Experiment Prediction if light Prediction if light Outcome
is a transverse wave s a longitudinal wave
The light reaching the other side of the polarizer is significantly dimmer.
Light from a lightbulb shines on a polarizer and its brightness is detected on the other side.
The same as above except the polarizer is slowly rotated.
The light reaching the other side of the polarizer is significantly dimmer and does not change as the polarizer is rotated.
Light from a lightbulb shines on a polarizer.
A second polarizer is positioned behind the first one. The second polarizer is slowly rotated relative to the first.
The light is dimmer overall but also fades in and out (depending on the angle) completely as the second polarizer is rotated.
b. Make a judgment about each of the two hypotheses. Which (if any) of them are disproved by these experiments?