The spectrum of light from a star is, to a good approximation, a blackbody spectrum. The red supergiant star Betelgeuse has Amax = 760 nm. (Note that this is actually in the infrared portion of the spectrum.) When light from Betelgeuse reaches the earth, the measured intensity at the earth is 2.9 X 108 W/m². Betelgeuse is located 490 light years from earth. (a) Find the temperature of Betelgeuse. (b) Find the intensity of light emitted by Betelgeuse. (Hint: Remember that this and the measured intensity at the earth are related by an inverse square law.) (c) Find the radius of Betelgeuse. (Assume it is spherical.)

The spectrum of light from a star is, to a good approximation, a blackbody spectrum. The red supergiant star Betelgeuse has Amax = 760 nm. (Note that this is actually in the infrared portion of the spectrum.) When light from Betelgeuse reaches the earth, the measured intensity at the earth is 2.9 X 108 W/m². Betelgeuse is located 490 light years from earth. (a) Find the temperature of Betelgeuse. (b) Find the intensity of light emitted by Betelgeuse. (Hint: Remember that this and the measured intensity at the earth are related by an inverse square law.) (c) Find the radius of Betelgeuse. (Assume it is spherical.)