Practice Test 1

A beam of light is passed through a polarizing filter. When a second filter is rotated, the transmitted brightness changes and can drop nearly to zero at certain angles. Which model best explains this behavior, and why?

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In a photoelectric experiment using the same metal, a student increases the light intensity while keeping the frequency fixed above the threshold. The number of emitted electrons per second increases, but the maximum kinetic energy of the electrons does not change. Which statement best matches the model needed to explain these observations?