UNIVERSE (LOOSELEAF):STARS+GALAXIES
6th Edition
ISBN: 9781319115043
Author: Freedman
Publisher: MAC HIGHER
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Chapter 18, Problem 18Q
To determine
The density of a Bok globule and comparison of the resultwith the density of a typical H II region.
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Consider the Milky Way disk, which has a 50 kpc diameter and a total height of 600 pc. Suppose
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Suppose a planetary nebula is 3.5 pc in diameter, and Doppler shifts in its spectrum show that the planetary nebula is expanding at 21 km/s. How old is the planetary nebula? (Note: 1 pc = 3.1 ✕ 1013 km and 1 yr = 3.2 ✕ 107 s.)
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Chapter 18 Solutions
UNIVERSE (LOOSELEAF):STARS+GALAXIES
Ch. 18 - Prob. 1QCh. 18 - Prob. 2QCh. 18 - Prob. 3QCh. 18 - Prob. 4QCh. 18 - Prob. 5QCh. 18 - Prob. 6QCh. 18 - Prob. 7QCh. 18 - Prob. 8QCh. 18 - Prob. 9QCh. 18 - Prob. 10Q
Ch. 18 - Prob. 11QCh. 18 - Prob. 12QCh. 18 - Prob. 13QCh. 18 - Prob. 14QCh. 18 - Prob. 15QCh. 18 - Prob. 16QCh. 18 - Prob. 17QCh. 18 - Prob. 18QCh. 18 - Prob. 19QCh. 18 - Prob. 20QCh. 18 - Prob. 21QCh. 18 - Prob. 22QCh. 18 - Prob. 23QCh. 18 - Prob. 24QCh. 18 - Prob. 25QCh. 18 - Prob. 26QCh. 18 - Prob. 27QCh. 18 - Prob. 28QCh. 18 - Prob. 29QCh. 18 - Prob. 30QCh. 18 - Prob. 31QCh. 18 - Prob. 32QCh. 18 - Prob. 33QCh. 18 - Prob. 34QCh. 18 - Prob. 35QCh. 18 - Prob. 36QCh. 18 - Prob. 37QCh. 18 - Prob. 38QCh. 18 - Prob. 39QCh. 18 - Prob. 40QCh. 18 - Prob. 41QCh. 18 - Prob. 42QCh. 18 - Prob. 43QCh. 18 - Prob. 44QCh. 18 - Prob. 45QCh. 18 - Prob. 46QCh. 18 - Prob. 47QCh. 18 - Prob. 48QCh. 18 - Prob. 49Q
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