Physics for Scientists and Engineers with Modern Physics
4th Edition
ISBN: 9780131495081
Author: Douglas C. Giancoli
Publisher: Addison-Wesley
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Chapter 44, Problem 42GP
To determine
The power output of the star.
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The star HD 69830's mass is 1.7 ✕ 1030 kg, its radius is 6.3 ✕ 105 km, and it has a rotational period of approximately 35 days. If HD 69830 should collapse into a white dwarf of radius 7.8 ✕ 103 km, what would its period (in s) be if no mass were ejected and a sphere of uniform density can model HD 69830 both before and after?
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A star has initially a radius of 660000000 m and a period of rotation about its axis of 34
days. Eventually it changes into a neutron star with a radius of only 35000 m and a period of
0.2 s. Assuming that the mass has not changed, find
Assume a star has the shape of a sphere.
(Suggestion: do it with formula first, then put the numbers in)
[Recommended time : 5-8 minutes]
(a) the ratio of initial to final angular momentum (Li/Lf)
Oa. 5.22E+15
Ob. 24.2
Oc. 0.0413
Od. 1.91E-16
(b) the ratio of initial to final kinetic energy
Oa. 1.3E-23
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Ob. 607000
Oc. 1.65E-6
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Chapter 44 Solutions
Physics for Scientists and Engineers with Modern Physics
Ch. 44.1 - Suppose we could place a huge mirror 1 light-year...Ch. 44.2 - Prob. 1BECh. 44.4 - What is the Schwarzschild radius for an object...Ch. 44.4 - A black hole has radius R. Its mass is...Ch. 44.9 - Prob. 1EECh. 44 - The Milky Way was once thought to be murky or...Ch. 44 - Prob. 2QCh. 44 - Prob. 3QCh. 44 - Prob. 4QCh. 44 - Prob. 5Q
Ch. 44 - Prob. 6QCh. 44 - Prob. 7QCh. 44 - Prob. 8QCh. 44 - Prob. 9QCh. 44 - Prob. 10QCh. 44 - Prob. 11QCh. 44 - Prob. 12QCh. 44 - Prob. 13QCh. 44 - Compare an explosion on Earth to the Big Bang....Ch. 44 - If nothing, not even light, escapes from a black...Ch. 44 - Prob. 16QCh. 44 - Prob. 17QCh. 44 - Explain what the 2.7-K cosmic microwave background...Ch. 44 - Prob. 19QCh. 44 - Prob. 20QCh. 44 - Prob. 21QCh. 44 - Under what circumstances would the universe...Ch. 44 - Prob. 23QCh. 44 - Prob. 24QCh. 44 - Prob. 1PCh. 44 - Prob. 2PCh. 44 - Prob. 3PCh. 44 - Prob. 4PCh. 44 - Prob. 5PCh. 44 - Prob. 6PCh. 44 - (II) What is the relative brightness of the Sun as...Ch. 44 - Prob. 8PCh. 44 - Prob. 9PCh. 44 - Prob. 10PCh. 44 - Prob. 11PCh. 44 - Prob. 12PCh. 44 - Prob. 13PCh. 44 - Prob. 14PCh. 44 - Prob. 15PCh. 44 - Prob. 16PCh. 44 - Prob. 17PCh. 44 - Prob. 18PCh. 44 - Prob. 19PCh. 44 - Prob. 20PCh. 44 - Prob. 21PCh. 44 - Prob. 22PCh. 44 - Prob. 23PCh. 44 - Prob. 24PCh. 44 - Prob. 25PCh. 44 - Prob. 26PCh. 44 - Prob. 27PCh. 44 - Prob. 28PCh. 44 - Prob. 29PCh. 44 - Prob. 30PCh. 44 - Prob. 31PCh. 44 - (II) Calculate the peak wavelength of the CMB at...Ch. 44 - Prob. 33PCh. 44 - (II) The scale factor or the universe (average...Ch. 44 - Prob. 35PCh. 44 - Prob. 36PCh. 44 - Prob. 37GPCh. 44 - Prob. 38GPCh. 44 - Prob. 39GPCh. 44 - Prob. 40GPCh. 44 - Prob. 41GPCh. 44 - Prob. 42GPCh. 44 - Prob. 43GPCh. 44 - Prob. 44GPCh. 44 - Prob. 45GPCh. 44 - Prob. 46GPCh. 44 - Prob. 47GPCh. 44 - Prob. 48GPCh. 44 - Prob. 49GPCh. 44 - Prob. 50GPCh. 44 - Calculate the Schwarzschild radius using a...Ch. 44 - How large would the Sun be if its density equaled...Ch. 44 - Prob. 53GPCh. 44 - (a) Use special relativity and Newtons law of...Ch. 44 - Prob. 55GPCh. 44 - Prob. 56GPCh. 44 - Prob. 57GPCh. 44 - Prob. 58GP
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