Question

A star has a surface temperature of 4500 K.
a. Calculate the peak wavelength of its brightness vs. wavelength curve. [1.5 points]

b. What color does this wavelength correspond to? (Note: See p. 5-7 of the textbook for a list of colors corresponding to different wavelength ranges. If the wavelength is in the infrared or ultraviolet range, state “IR” or “UV” as the color.) [0.5 points]

c. Now imagine that the star is moving away from us at 0.15c, where c is the speed of light. What peak wavelength would we observe in this case? [1.5 points]

d. What color does the peak wavelength obtained in part (c) correspond to? (See note in part b.) [0.5 points]

Answer 1