Understanding Our Universe
3rd Edition
ISBN: 9780393614428
Author: PALEN, Stacy, Kay, Laura, Blumenthal, George (george Ray)
Publisher: W.w. Norton & Company,
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Chapter 17, Problem 34QAP
To determine
Difficulties to model star formation.
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Suppose you want to observe the molecular gas in a galaxy with redshift z using the rotational transition of CO J=4-3. What frequency would you observe this transition at? (Hint: the CO J=1-0 emits a photon at 115.27 GHz, and higher order transitions emit photons with frequencies in multiples of J, e.g., use the knowledge you gained from the problem above). Express your answer as an integer.
Values:
z = 1.3
Among the globular clusters orbiting a distant galaxy, one is moving at 534 km/s and is located 14 kpc from the center of the galaxy. Assuming the globular cluster is located outside most of the mass of the galaxy, what is the mass of the galaxy? Convert your answer to solar masses. (Hint: Use the formula for circular velocity,
Vc =
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r
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make sure you convert relevant quantities to units of meters, kilograms, and seconds. Note: 1 pc = 3.1 ✕ 1016 m.)
As we discussed, clouds are made of a great many small drops. Really - a great many. Imagine a
liquid cloud that fills a volume of 1 km3. The clouds contains 100 drops per cubic centimeter; for
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power
Chapter 17 Solutions
Understanding Our Universe
Ch. 17.1 - Prob. 17.1CYUCh. 17.2 - Prob. 17.2CYUCh. 17.3 - Prob. 17.3CYUCh. 17.4 - Prob. 17.4CYUCh. 17.5 - Prob. 17.5CYUCh. 17 - Prob. 1QAPCh. 17 - Prob. 2QAPCh. 17 - Prob. 3QAPCh. 17 - Prob. 4QAPCh. 17 - Prob. 5QAP
Ch. 17 - Prob. 6QAPCh. 17 - Prob. 7QAPCh. 17 - Prob. 8QAPCh. 17 - Prob. 9QAPCh. 17 - Prob. 10QAPCh. 17 - Prob. 11QAPCh. 17 - Prob. 12QAPCh. 17 - Prob. 13QAPCh. 17 - Prob. 14QAPCh. 17 - Prob. 15QAPCh. 17 - Prob. 16QAPCh. 17 - Prob. 17QAPCh. 17 - Prob. 18QAPCh. 17 - Prob. 19QAPCh. 17 - Prob. 20QAPCh. 17 - Prob. 21QAPCh. 17 - Prob. 22QAPCh. 17 - Prob. 23QAPCh. 17 - Prob. 24QAPCh. 17 - Prob. 25QAPCh. 17 - Prob. 26QAPCh. 17 - Prob. 27QAPCh. 17 - Prob. 28QAPCh. 17 - Prob. 29QAPCh. 17 - Prob. 30QAPCh. 17 - Prob. 31QAPCh. 17 - Prob. 32QAPCh. 17 - Prob. 33QAPCh. 17 - Prob. 34QAPCh. 17 - Prob. 35QAPCh. 17 - Prob. 36QAPCh. 17 - Prob. 37QAPCh. 17 - Prob. 38QAPCh. 17 - Prob. 39QAPCh. 17 - Prob. 40QAPCh. 17 - Prob. 41QAPCh. 17 - Prob. 42QAPCh. 17 - Prob. 43QAPCh. 17 - Prob. 44QAPCh. 17 - Prob. 45QAP
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