Foundations of Astronomy (MindTap Course List)
14th Edition
ISBN: 9781337399920
Author: Michael A. Seeds, Dana Backman
Publisher: Cengage Learning
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Chapter 12, Problem 4P
To determine
The lifetime ratio of main-sequences of Star A and Star B.
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For a main sequence star with luminosity L, how many kilograms of hydrogen is being converted into helium per second? Use the formula that you derive to estimate the mass of hydrogen atoms that are converted into helium in the interior of the sun (LSun = 3.9 x 1026 W).
(Note: the mass of a hydrogen atom is 1 mproton and the mass of a helium atom is 3.97 mproton. You need four hydrogen nuclei to form one helium nucleus.)
Star A and Star B are both on the main sequence. Star A is 63 times more luminous than Star B. What is the ratio of their main-sequence lifetimes?
Hint: Refer to the stellar life expectancies equation,
t* =
M*
L*
=
M*
M*3.5
=
1
M*2.5
.
Star A and Star B are both on the main sequence. Star A is 74 times more luminous than Star B. What is the ratio of their main-sequence lifetimes?
Hint: Refer to the stellar life expectancies equation,
Chapter 12 Solutions
Foundations of Astronomy (MindTap Course List)
Ch. 12 - Prob. 1RQCh. 12 - Prob. 2RQCh. 12 - Prob. 3RQCh. 12 - Prob. 4RQCh. 12 - Prob. 5RQCh. 12 - Describe the law of hydrostatic equilibrium.Ch. 12 - Prob. 7RQCh. 12 - Prob. 8RQCh. 12 - Prob. 9RQCh. 12 - Prob. 10RQ
Ch. 12 - Prob. 11RQCh. 12 - Prob. 12RQCh. 12 - Prob. 13RQCh. 12 - Prob. 14RQCh. 12 - Prob. 15RQCh. 12 - Prob. 16RQCh. 12 - Prob. 17RQCh. 12 - Prob. 18RQCh. 12 - Prob. 19RQCh. 12 - What gives the triple-alpha process its name? Why...Ch. 12 - Prob. 21RQCh. 12 - Prob. 22RQCh. 12 - Prob. 23RQCh. 12 - Prob. 24RQCh. 12 - Prob. 25RQCh. 12 - Prob. 26RQCh. 12 - Prob. 27RQCh. 12 - Prob. 28RQCh. 12 - Prob. 29RQCh. 12 - Prob. 30RQCh. 12 - Prob. 31RQCh. 12 - How Do We Know? How can mathematical models allow...Ch. 12 - Prob. 1PCh. 12 - Prob. 2PCh. 12 - Prob. 3PCh. 12 - Prob. 4PCh. 12 - Prob. 5PCh. 12 - Prob. 6PCh. 12 - Prob. 7PCh. 12 - Prob. 8PCh. 12 - Prob. 9PCh. 12 - Prob. 10PCh. 12 - Prob. 11PCh. 12 - Prob. 12PCh. 12 - Prob. 13PCh. 12 - Prob. 14PCh. 12 - Prob. 15PCh. 12 - Prob. 16PCh. 12 - Prob. 1SOPCh. 12 - Prob. 2SOPCh. 12 - Prob. 1LTLCh. 12 - Prob. 2LTLCh. 12 - Prob. 3LTLCh. 12 - Prob. 4LTLCh. 12 - Prob. 5LTL
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