Horizons: Exploring the Universe (MindTap Course List)
14th Edition
ISBN: 9781305960961
Author: Michael A. Seeds, Dana Backman
Publisher: Cengage Learning
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Chapter 9, Problem 1P
To determine
What fraction of photons survive a trip of 1000 pc?
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What is the ratio of the percent of metals in extreme Population I stars (3%) to that in extreme Population II stars (0.05%)?
NpopI
NpopII
=
A planetary nebula expanded in radius 0.3 arc seconds in 30 years. Doppler measurements show the nebula is expanding at a rate of 35 km/s. How far away is the nebula in parsecs?
First, determine what distance the nebular expanded in parsecs during the time mentioned. Δd = vpc/sTs
So we first need to convert the rate into pc/s and the time into seconds:
vpc/s = vkm/s (1 pc / 3.09 x 1013km)
vpc/s = ?
Ts = (Tyr)(365 days/yr)(24 hrs/day)(3600 s/hr)
Ts = ? s
Δd= vpc/sTs
Therefore, Δd = ? pc
Interstellar extinction dims starlight by about 1 magnitude per 1000 pc.
What fraction of photons survives a trip of 1000 pc?
Chapter 9 Solutions
Horizons: Exploring the Universe (MindTap Course List)
Ch. 9 - Prob. 1RQCh. 9 - Why evidence can you cite that the interstellar...Ch. 9 - Prob. 3RQCh. 9 - Prob. 4RQCh. 9 - Prob. 5RQCh. 9 - Prob. 6RQCh. 9 - Prob. 7RQCh. 9 - Prob. 8RQCh. 9 - Prob. 9RQCh. 9 - Prob. 10RQ
Ch. 9 - Prob. 11RQCh. 9 - Prob. 12RQCh. 9 - How does the CNO cycle differ from the...Ch. 9 - Prob. 14RQCh. 9 - Step-by-step, explain how energy flows from the...Ch. 9 - Prob. 16RQCh. 9 - Prob. 17RQCh. 9 - Prob. 18RQCh. 9 - Prob. 19RQCh. 9 - Prob. 20RQCh. 9 - Prob. 1DQCh. 9 - What is your favorite home-cooked meal? In terms...Ch. 9 - Prob. 3DQCh. 9 - How does hydrostatic equilibrium relate to hot-air...Ch. 9 - Prob. 1PCh. 9 - Prob. 2PCh. 9 - Prob. 3PCh. 9 - Prob. 4PCh. 9 - Prob. 5PCh. 9 - Prob. 6PCh. 9 - Prob. 7PCh. 9 - Prob. 8PCh. 9 - Prob. 9PCh. 9 - Prob. 10PCh. 9 - If a protostellar disk is 200 AU in radius and the...Ch. 9 - Prob. 12PCh. 9 - Prob. 13PCh. 9 - Prob. 14PCh. 9 - H much energy is produced when the CNO cycle...Ch. 9 - Prob. 16PCh. 9 - Prob. 1LTLCh. 9 - Prob. 2LTL
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