21st Century Astronomy
6th Edition
ISBN: 9780393428063
Author: Kay
Publisher: NORTON
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Chapter 21, Problem 1QP
To determine
The reason why the astronomers say that the universe is homogeneous.
Expert Solution & Answer
Answer to Problem 1QP
Option (d).
Explanation of Solution
The meaning of word homogeneous is same in all locations. Based on cosmological principle the universe is both homogeneous and isotropic.
The universe appears homogeneous when it is viewed in large scale, because the forces are expected to act uniformly throughout the universe. Hence there is no irregularity in large scale structure.
Conclusion:
Since the universe appears same in all locations option (d) is the best suited answer.
Since the universe appears same in all locations option (a) is not the correct answer.
Since the universe appears same in all locations option (b) is not the correct answer.
Since the universe appears same in all locations option (c) is not the correct answer.
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Students have asked these similar questions
If our universe is expanding, what are the implications for the separation between two stars within our galaxy?
A.
The two stars are moving farther apart.
B.
The two stars are moving closer together.
C.
The distance between the two stars is unaffected.
D.
The question is impossible to answer without more information.
The age of the universe can be determined if
a.
the universe is flat.
b.
the amount of dark matter in the universe can be accurately determined.
c.
the rate of recession of the galaxies in the Local Group can be accurately determined.
d.
the temperature of the cosmic background radiation can be accurately determined.
e.
the Hubble constant and density of the universe can be accurately determined.
An astronomer observed the motions of some galaxies. Based on his observations, he made the following statements. Which one of them is most likely to be false? Take Hubble's constant to be 67 km/s/Mpc.
A. A galaxy observed to be moving away from us at a speed of 70 km/s is at a distance of about 1 Mpc from us.
B. A galaxy observed to be moving away from us at a speed of 700 km/s is at a distance of about 10 Mpc from us.
C. A galaxy observed to be moving away from us at a speed of 7000 km/s is at a distance of about 100 Mpc from us.
D. A galaxy observed to be moving away from us at a speed of 70000 km/s is at a distance of about 1 Gpc from us.
Is the answer D? Thank you!
Chapter 21 Solutions
21st Century Astronomy
Ch. 21.1 - Prob. 21.1CYUCh. 21.2 - Prob. 21.2CYUCh. 21.3 - Prob. 21.3ACYUCh. 21.3 - Prob. 21.3BCYUCh. 21.4 - Prob. 21.4CYUCh. 21 - Prob. 1QPCh. 21 - Prob. 2QPCh. 21 - Prob. 3QPCh. 21 - Prob. 4QPCh. 21 - Prob. 5QP
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