Astronomy Today (9th Edition)
9th Edition
ISBN: 9780134450278
Author: Eric Chaisson, Steve McMillan
Publisher: PEARSON
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Chapter 3, Problem 8P
To determine
The recession velocity of Alpha Centauri relative to the Sun, if the
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Small differences in the wavelengths in the sun’s spectrum are detected when measurements are taken from different parts of the sun’s disk. Specifi cally, measurements of the 656-nm line in hydrogen taken from opposite sides on the sun’s equator—one side approaching Earth and the other receding—differ from each other by 0.0090 nm. Use this information to fi nd the rotational period of the sun’s equator. Express your answer in days. (The sun’s equatorial radius is 6.96 x 108 m.)
A blue supergiant star has a radius of 7.4 x 1010 m. The spherical surface behaves like a blackbody radiator. If the blue supergiant star radiates an
energy rate of 1.29 × 1033 w, what would be its surface temperature (in °C)? The Stefan-Boltzmann constant is 5.67 × 10-8 w/(m2 . K4).
A star such as our Sun will eventually evolve to a “red giant” star and then to a “white dwarf” star. A typical white dwarf is approximately the size of Earth, and its surface temperature is about 2.4 × 104 K. A typical red giant has a surface temperature of 3.2 × 103 K and a radius ~90000 times larger than that of a white dwarf. Take the radius of the red giant to be 6 × 1010 m.
What is the average radiated power per unit area of the red giant?_________W/m2
What is the average radiated power per unit area of the white-dwarf?________W/m2
What is the total power radiated by the red giant? _________W
What is the total power radiated by the white dwarf? ________W
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Chapter 3 Solutions
Astronomy Today (9th Edition)
Ch. 3 - Prob. 1DCh. 3 - Prob. 2DCh. 3 - Prob. 3DCh. 3 - Prob. 4DCh. 3 - Prob. 5DCh. 3 - Prob. 6DCh. 3 - Prob. 7DCh. 3 - Prob. 8DCh. 3 - Prob. 9DCh. 3 - Prob. 10D
Ch. 3 - Prob. 11DCh. 3 - Prob. 12DCh. 3 - Prob. 13DCh. 3 - Prob. 14DCh. 3 - Prob. 15DCh. 3 - Prob. 1MCCh. 3 - Prob. 2MCCh. 3 - Prob. 3MCCh. 3 - Prob. 4MCCh. 3 - Prob. 5MCCh. 3 - Prob. 6MCCh. 3 - Prob. 7MCCh. 3 - Prob. 8MCCh. 3 - Prob. 9MCCh. 3 - Prob. 10MCCh. 3 - Prob. 1PCh. 3 - Prob. 2PCh. 3 - Prob. 3PCh. 3 - Prob. 4PCh. 3 - Prob. 5PCh. 3 - Prob. 6PCh. 3 - Prob. 7PCh. 3 - Prob. 8P
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