If a beam of blue light with a wavelength of 400 nm is emitted by an object moving awayfrom you at $1 \%$ o the speed of light, what wavelength would you see from this light?
A)396 nm
B)399 nm
C)400 nm
D)401 nm
E)404 nm

Question

Quizplus · Accepted Answer

The correct answer is A because the wavelength of light is shortened when the source of light is moving away from the observer. The amount of shortening is proportional to the speed of the source. In this case, the source is moving away from the observer at 1% of the speed of light, so the wavelength of light will be shortened by 1%. This means that the wavelength of light will be 400 nm * (1 - 0.01) = 396 nm.

If a Beam of Blue Light with a Wavelength of 400