UNDERSTANDING THE UNIVERSE(LL)-W/CODE
3rd Edition
ISBN: 9780393869903
Author: PALEN
Publisher: NORTON
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Chapter 12, Problem 11QAP
To determine
The changes in luminosity and temperature of protostar convert into low mass star.
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Betelgeuse is a nearby supergiant that will eventually explode into a supernova. Let's see
how awesome it would look. At peak brightness, the supernova will have a luminosity of
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of 25 light-years, an absolute magnitude of 0.6 and an apparent magnitude of 0 (by
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a) At peak brightness, how many times brighter will Betelgeuse be than Vega?
b) Approximately what apparent magnitude does this correspond to?
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Betelgeuse be?
The mass-luminosity relation describes the mathematical relationship between luminosity and mass for main sequence stars. It describes how a star with a mass of 4 M⊙ would have a luminosity of ______ L⊙.
If a star has a radius 1/2 that of the Sun and a temperature 4 that of the Sun, how many times higher is the star's luminosity than that of the Sun? (If it is smaller by a factor of 8, you would write 0.125 because 1/8=0.125)
If a star has a radius 2 times larger than the Sun's and a luminosity 1/4th that of the Sun, how many times higher is the star's temperature than that of the Sun? (If it is smaller by a factor of 8, you would write 0.125 because 1/8=0.125)
If a star has a surface temperature 2 times lower than the Sun's and a luminosity the same as the Sun, how many times larger is the star than the Sun? (If it is smaller by a factor of 8, you would write 0.125 because 1/8=0.125)
Using solar units, we find that a star has 4 times the luminosity of the Sun, a mass 1.25 times the mass of the Sun, and a surface temperature of 4090 K (take the Sun's surface temperature to be 5784 K for the sake of this problem). This means the star has a radius of.................... solar radii and is a .................... star (use the classification).
Chapter 12 Solutions
UNDERSTANDING THE UNIVERSE(LL)-W/CODE
Ch. 12.1 - Prob. 12.1CYUCh. 12.2 - Prob. 12.2CYUCh. 12.3 - Prob. 12.3CYUCh. 12.4 - Prob. 12.4CYUCh. 12.5 - Prob. 12.5CYUCh. 12.6 - Prob. 12.6CYUCh. 12 - Prob. 1QAPCh. 12 - Prob. 2QAPCh. 12 - Prob. 3QAPCh. 12 - Prob. 4QAP
Ch. 12 - Prob. 5QAPCh. 12 - Prob. 6QAPCh. 12 - Prob. 7QAPCh. 12 - Prob. 8QAPCh. 12 - Prob. 9QAPCh. 12 - Prob. 10QAPCh. 12 - Prob. 11QAPCh. 12 - Prob. 12QAPCh. 12 - Prob. 13QAPCh. 12 - Prob. 14QAPCh. 12 - Prob. 15QAPCh. 12 - Prob. 16QAPCh. 12 - Prob. 17QAPCh. 12 - Prob. 18QAPCh. 12 - Prob. 19QAPCh. 12 - Prob. 20QAPCh. 12 - Prob. 21QAPCh. 12 - Prob. 22QAPCh. 12 - Prob. 23QAPCh. 12 - Prob. 24QAPCh. 12 - Prob. 25QAPCh. 12 - Prob. 26QAPCh. 12 - Prob. 27QAPCh. 12 - Prob. 28QAPCh. 12 - Prob. 29QAPCh. 12 - Prob. 30QAPCh. 12 - Prob. 32QAPCh. 12 - Prob. 33QAPCh. 12 - Prob. 34QAPCh. 12 - Prob. 35QAPCh. 12 - Prob. 36QAPCh. 12 - Prob. 37QAPCh. 12 - Prob. 38QAPCh. 12 - Prob. 39QAPCh. 12 - Prob. 40QAPCh. 12 - Prob. 42QAPCh. 12 - Prob. 43QAPCh. 12 - Prob. 44QAPCh. 12 - Prob. 45QAP
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