The light from a distant star is shifted such that the peak of its spectrum, at 620 nm ,is shifted to 635 nm.What is its radial velocity relative to Earth?
A) -0.11c
B) -0.024c
C) -0.15c
D) -0.012c

Question

Quizplus · Accepted Answer

The radial velocity is given by v = c * (lambda_obs - lambda_rest) / lambda_rest, where c is the speed of light, lambda_obs is the observed wavelength, and lambda_rest is the rest wavelength. Plugging in the given values, we get v = c * (635 nm - 620 nm) / 620 nm = -0.024c.

The Light from a Distant Star Is Shifted Such That