EP COSMIC PERSPECTIVE-MOD.MASTERING
9th Edition
ISBN: 9780137453481
Author: Bennett
Publisher: SAVVAS L
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Chapter 23, Problem 58EAP
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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!
Hubble's First Attempt. Edwin Hubble's first attempt to measure the universe's expansion rate was flawed because the standard candles he was using were not properly calibrated. Look at (Figure 1)
a.Estimate the value of Ho corresponding to the solid line in the figure. Express your answer kilometers per second per million light-years to two significant figures.
b.What is the approximate age of the universe indicated by that erroneous value of Ho? Express your answer in years to one significant figure.
7. How large is our supermassive black hole in terms of the size of the Earth’s orbit? (Divide the radius of Sagittarius A* (i.e., your result in Question 6) in meters by 1 AU(1 AU =1.5 x 1011 m) to see how large our supermassive black hole is in terms of the size of the Earth’s orbit. Note that the size of Earth’s orbit is defined as 1 AU). Your result will be in AU (Just submit your answer, do not submit the unit AU).
Chapter 23 Solutions
EP COSMIC PERSPECTIVE-MOD.MASTERING
Ch. 23 - Prob. 1VSCCh. 23 - Prob. 2VSCCh. 23 - Prob. 3VSCCh. 23 - Prob. 4VSCCh. 23 - Prob. 1EAPCh. 23 - Prob. 2EAPCh. 23 - Prob. 3EAPCh. 23 - Prob. 4EAPCh. 23 - Prob. 5EAPCh. 23 - Prob. 6EAP
Ch. 23 - Prob. 7EAPCh. 23 - Prob. 8EAPCh. 23 - Prob. 9EAPCh. 23 - Explain what we mean when we say that a neutrino...Ch. 23 - Prob. 11EAPCh. 23 - Briefly explain why dark matter is thought to have...Ch. 23 - What do the large-scale structures of the universe...Ch. 23 - Prob. 14EAPCh. 23 - Prob. 15EAPCh. 23 - Prob. 16EAPCh. 23 - Prob. 17EAPCh. 23 - Prob. 18EAPCh. 23 - Prob. 19EAPCh. 23 - Prob. 20EAPCh. 23 - Prob. 21EAPCh. 23 - Prob. 22EAPCh. 23 - Prob. 23EAPCh. 23 - Prob. 24EAPCh. 23 - Prob. 25EAPCh. 23 - Prob. 26EAPCh. 23 - Prob. 27EAPCh. 23 - Prob. 28EAPCh. 23 - Prob. 29EAPCh. 23 - Prob. 30EAPCh. 23 - Choose the best answer to each of the following....Ch. 23 - Prob. 32EAPCh. 23 - Prob. 33EAPCh. 23 - Prob. 34EAPCh. 23 - Choose the best answer to each of the following....Ch. 23 - Choose the best answer to each of the following....Ch. 23 - Choose the best answer to each of the following....Ch. 23 - Prob. 38EAPCh. 23 - Prob. 40EAPCh. 23 - Prob. 43EAPCh. 23 - Prob. 44EAPCh. 23 - Prob. 45EAPCh. 23 - Prob. 46EAPCh. 23 - Prob. 47EAPCh. 23 - Prob. 48EAPCh. 23 - Prob. 49EAPCh. 23 - Prob. 50EAPCh. 23 - Prob. 51EAPCh. 23 - Prob. 52EAPCh. 23 - Prob. 53EAPCh. 23 - Prob. 54EAPCh. 23 - Prob. 55EAPCh. 23 - Weighing a Cluster. A cluster of galaxies has a...Ch. 23 - Prob. 57EAPCh. 23 - Prob. 58EAPCh. 23 - Prob. 59EAP
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