Foundations of Astronomy (MindTap Course List)
14th Edition
ISBN: 9781337399920
Author: Michael A. Seeds, Dana Backman
Publisher: Cengage Learning
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Chapter 17, Problem 8P
To determine
The average density of the matter in the universe and the model of the universe.
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Pretend that galaxies are spaced evenly, 7.0 Mpc apart, and the average mass of a galaxy is 1.0 ✕ 1011 M. What is the average density (in kg/m3) of matter in the universe? (Note: The volume of a sphere is 4/3pieR^3 and the mass of the sun is 2.0 ✕ 1030 kg.)
______ kg/m^3
Which model universe does this density value support?
A: open
B: flat
C: closed
Pretend that galaxies are spaced evenly, 8.0 Mpc apart, and the average mass of a galaxy is 1.0 ✕ 1011 M. What is the average density (in kg/m3) of matter in the universe?
Which model universe does this density value support?
Pretend that galaxies are spaced evenly, 4.0 Mpc apart, and the average mass of a galaxy is 1.0 x 101 M
What is the average density (in kg/m³) of matter in the universe? (Note: The volume of a
sphere is
4
-ar, and the mass of the sun is 2.0 x 1030 kg.)
kg/m3
Which model universe does this density value support?
flat
open
closed
Chapter 17 Solutions
Foundations of Astronomy (MindTap Course List)
Ch. 17 - Is cosmology the study of the Universe, the...Ch. 17 - Is a cosmologist an astronomer? Is an astronomer a...Ch. 17 - How does the darkness of the night sky tell you...Ch. 17 - Explain the differences among the observable...Ch. 17 - Prob. 5RQCh. 17 - Prob. 6RQCh. 17 - Prob. 7RQCh. 17 - Prob. 8RQCh. 17 - Prob. 9RQCh. 17 - Prob. 10RQ
Ch. 17 - Prob. 11RQCh. 17 - If you accept the cosmological principle, how can...Ch. 17 - Why cant an open universe have a center? How can a...Ch. 17 - In which type of model universe is space-time...Ch. 17 - In which type of model universe is space-time...Ch. 17 - What is the fate of a closed universe? In what...Ch. 17 - In which model universe does the average density...Ch. 17 - Prob. 18RQCh. 17 - What evidence shows that the Universe is...Ch. 17 - Why couldnt atomic nuclei exist when the Universe...Ch. 17 - Why are measurements of the current density of the...Ch. 17 - What percentage of matter is ordinary matter? What...Ch. 17 - How does the inflationary universe hypothesis...Ch. 17 - Prob. 24RQCh. 17 - What is the evidence that the Universe was...Ch. 17 - Prob. 26RQCh. 17 - If the Universe is negatively curved, and dark...Ch. 17 - What is the difference between hot dark matter and...Ch. 17 - Prob. 29RQCh. 17 - What evidence can you cite that the Universe's...Ch. 17 - Prob. 31RQCh. 17 - Reasoning by analogy often helps make complicated...Ch. 17 - Prob. 33RQCh. 17 - In science, wishing something to be true does not...Ch. 17 - Prob. 1PCh. 17 - Prob. 2PCh. 17 - Prob. 3PCh. 17 - Measure the lengths of the two arrows in the left...Ch. 17 - Prob. 5PCh. 17 - Prob. 6PCh. 17 - Find the wavelength of maximum intensity of the...Ch. 17 - Prob. 8PCh. 17 - Prob. 9PCh. 17 - Prob. 10PCh. 17 - Prob. 11PCh. 17 - Prob. 12PCh. 17 - Prob. 1SOPCh. 17 - Prob. 2SOPCh. 17 - Prob. 1LTLCh. 17 - Prob. 2LTLCh. 17 - Prob. 3LTLCh. 17 - Prob. 4LTLCh. 17 - Prob. 5LTLCh. 17 - Prob. 6LTL
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