A research laboratory has two monochromatic light sources that operate in a vacuum
PHYSICS · Multi-part · AP · Physics 2: Algebra-based · Waves Sound and Physical Optics · Waves Sound and Physical Optics
Problem
A research laboratory has two monochromatic light sources that operate in a vacuum. Source I emits light with a wavelength of 720 nm, while Source II is adjusted so that its wavelength is exactly one-half that of Source I.
Answer the following questions about the relationship between the two sources. No numerical calculations are required.
(a) Describe how the frequency of the radiation from Source II compares with that from Source I.
(b) Suppose a third source is tuned so that its wavelength is one-third that of Source I (still in a vacuum). Using proportional reasoning, explain how its frequency would compare with the frequency of Source I.
(c) Explain qualitatively how the photon energy for the radiation described in part (b) compares with the photon energy for Source I. Justify your answer in terms of the relevant physical relationship(s).