Essential Cosmic Perspective
9th Edition
ISBN: 9780135795033
Author: Bennett
Publisher: PEARSON
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Chapter 1, Problem 50EAP
Age of the Universe. Suppose we did not yet know the expansion rate of the universe, and two astronomers came up with two dif-ferent measurements: Wendy measured an expansion rate for the universe that was 50% faster than the expansion rate Allan measured. Was the age of the universe that Allan inferred older or younger than the age that Wendy inferred? By how much? Explain. (Hint: Read the discussion of the raisin cake analogy carefully, and the answer should become clear.)
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Chapter 1 Solutions
Essential Cosmic Perspective
Ch. 1 - Prob. 1VSCCh. 1 - Prob. 2VSCCh. 1 - About how far away from Earth would the Sun be...Ch. 1 - Prob. 4VSCCh. 1 - Prob. 1EAPCh. 1 - Define astronomical unit and light-year.Ch. 1 - Explain the statement The farther away we look in...Ch. 1 - Prob. 4EAPCh. 1 - Prob. 5EAPCh. 1 - What do we mean when we say that the universe is...
Ch. 1 - In what sense are we “star stuff”?Ch. 1 - Use the cosmic calendar to describe how the human...Ch. 1 - Briefly explain Earth’s daily rotation and annual...Ch. 1 - Prob. 10EAPCh. 1 - Prob. 11EAPCh. 1 - Prob. 12EAPCh. 1 - Prob. 13EAPCh. 1 - Prob. 14EAPCh. 1 - Decide whether the statement makes sense (or is...Ch. 1 - Prob. 16EAPCh. 1 - Prob. 17EAPCh. 1 - Prob. 18EAPCh. 1 - Decide whether the statement makes sense (or is...Ch. 1 - Prob. 20EAPCh. 1 - Decide whether the statement makes sense (or is...Ch. 1 - Prob. 22EAPCh. 1 - Prob. 23EAPCh. 1 - An astronomical unit is (a) any planet’s average...Ch. 1 - The star Betelgeuse s about 600 light-years away....Ch. 1 - Prob. 26EAPCh. 1 - Prob. 27EAPCh. 1 - Prob. 28EAPCh. 1 - Prob. 29EAPCh. 1 - Prob. 30EAPCh. 1 - Prob. 31EAPCh. 1 - Prob. 32EAPCh. 1 - Prob. 34EAPCh. 1 - Thinking About Scale. One key to success m science...Ch. 1 - Prob. 36EAPCh. 1 - A Human Adventure. Astronomical discoveries...Ch. 1 - Prob. 38EAPCh. 1 - Group Activity: Counting the Milky Way’s Stars....Ch. 1 - Prob. 40EAPCh. 1 - Prob. 41EAPCh. 1 - Prob. 42EAPCh. 1 - Prob. 43EAPCh. 1 - Prob. 44EAPCh. 1 - Moonlight and Sunlight. How long does it take...Ch. 1 - Prob. 46EAPCh. 1 - Driving Trips. Imagine that you could drive your...Ch. 1 - Prob. 48EAPCh. 1 - Prob. 49EAPCh. 1 - Age of the Universe. Suppose we did not yet know...
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
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- For the graph shown above, a) what quantity would you label the y-axis with if the distance is between galaxies and the Earth? Explain your answer. Think through what we know is happening, motion-wise, out there in the galaxy. b) Also explain why you think there are dots and a solid line, on the graph.arrow_forwardStars form in the Milky Way at a rate of about 1 solar mass per year. At this rate, how long would it take for all the interstellar gas in the Milky Way to be turned into stars if there were no fresh gas coming in from outside? How does this compare to the estimated age of the universe, 14 billion years? What do you conclude from this?arrow_forwardWhat does it mean to say that the universe is expanding? What is expanding? For example, is your astronomy classroom expanding? Is the solar system? Why or why not?arrow_forward
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- What evidence shows that the Universe is expanding? What evidence shows that the Universe began with a Big Bang?arrow_forwardUsing our example from the previous unit, let's try to determine the Hubble time for this example universe. You were given that a good representative galaxy receded at a speed of 4000 km/s and was found to be 20 Mpc away. With that in mind, what would the age of that universe be in years (aka what is that universe's Hubble time)? Go ahead and take the number of kilometers per Mpc to be approximately 3.1*10^19 km/Mpc. While this problem may look scary at first, this is really just bringing you full circle to one of the unit conversion problems you encountered at the beginning of this course.arrow_forwardState three pieces of evidence that support the idea that the Universe began in a hot Big Bang, and explain how each piece of evidence supports the hot Big Bang model. Describe the ob- servational evidence that supports the idea that the Universe is pervaded by Dark Energy, and explain why each piece of evidence you cite supports the Dark Energy model.arrow_forward
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