PHYSICS F./SCI... W/MOD V.II W/KIT
4th Edition
ISBN: 9780134819884
Author: GIANCOLI
Publisher: PEARSON
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Chapter 44, Problem 24Q
(a)
To determine
The reason for expecting decreasing expansion rate of universe by the astronomers.
(b)
To determine
The way by which the astronomers hope to determine whether the universe used to expand faster than it does now.
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The visible section of the Universe is a sphere centered on the bridge of your nose, with radius 13.7 billion light-years. (a) Explain why the visible Universe is getting larger, with its radius increasing by one light-year in every year. (b) Find the rate at which the volume of the visible section of the Universe is increasing.
To get an idea of how empty deep space is on the average, perform the following calculations:
(a) Find the volume our Sun would occupy if it had an average density equal to the critical density of 10-26 kg / m3 thought necessary to halt the expansion of the universe.
(b) Find the radius of a sphere of this volume in light years.
(c) What would this radius be if the density were that of luminous matter, which is approximately 5% that of the critical density?
(d) Compare the radius found in part (c) with the 4-ly average separation of stars in the arms of the Milky Way.
(a) Calculate the approximate age of the universe from the average value of the Hubble constant, H0 = 20km/s ⋅ Mly . To do this, calculate the time it would take to travel 1 Mly at a constant expansion rate of 20 km/s. (b) If deceleration is taken into account, would the actual age of the universe be greater or less than that found here? Explain.
Chapter 44 Solutions
PHYSICS F./SCI... W/MOD V.II W/KIT
Ch. 44.1 - Suppose we could place a huge mirror 1 light-year...Ch. 44.2 - Prob. 1BECh. 44.4 - What is the Schwarzschild radius for an object...Ch. 44.4 - A black hole has radius R. Its mass is...Ch. 44.9 - Prob. 1EECh. 44 - The Milky Way was once thought to be murky or...Ch. 44 - Prob. 2QCh. 44 - Prob. 3QCh. 44 - Prob. 4QCh. 44 - Prob. 5Q
Ch. 44 - Prob. 6QCh. 44 - Prob. 7QCh. 44 - Prob. 8QCh. 44 - Prob. 9QCh. 44 - Prob. 10QCh. 44 - Prob. 11QCh. 44 - Prob. 12QCh. 44 - Prob. 13QCh. 44 - Compare an explosion on Earth to the Big Bang....Ch. 44 - If nothing, not even light, escapes from a black...Ch. 44 - Prob. 16QCh. 44 - Prob. 17QCh. 44 - Explain what the 2.7-K cosmic microwave background...Ch. 44 - Prob. 19QCh. 44 - Prob. 20QCh. 44 - Prob. 21QCh. 44 - Under what circumstances would the universe...Ch. 44 - Prob. 23QCh. 44 - Prob. 24QCh. 44 - Prob. 1PCh. 44 - Prob. 2PCh. 44 - Prob. 3PCh. 44 - Prob. 4PCh. 44 - Prob. 5PCh. 44 - Prob. 6PCh. 44 - (II) What is the relative brightness of the Sun as...Ch. 44 - Prob. 8PCh. 44 - Prob. 9PCh. 44 - Prob. 10PCh. 44 - Prob. 11PCh. 44 - Prob. 12PCh. 44 - Prob. 13PCh. 44 - Prob. 14PCh. 44 - Prob. 15PCh. 44 - Prob. 16PCh. 44 - Prob. 17PCh. 44 - Prob. 18PCh. 44 - Prob. 19PCh. 44 - Prob. 20PCh. 44 - Prob. 21PCh. 44 - Prob. 22PCh. 44 - Prob. 23PCh. 44 - Prob. 24PCh. 44 - Prob. 25PCh. 44 - Prob. 26PCh. 44 - Prob. 27PCh. 44 - Prob. 28PCh. 44 - Prob. 29PCh. 44 - Prob. 30PCh. 44 - Prob. 31PCh. 44 - (II) Calculate the peak wavelength of the CMB at...Ch. 44 - Prob. 33PCh. 44 - (II) The scale factor or the universe (average...Ch. 44 - Prob. 35PCh. 44 - Prob. 36PCh. 44 - Prob. 37GPCh. 44 - Prob. 38GPCh. 44 - Prob. 39GPCh. 44 - Prob. 40GPCh. 44 - Prob. 41GPCh. 44 - Prob. 42GPCh. 44 - Prob. 43GPCh. 44 - Prob. 44GPCh. 44 - Prob. 45GPCh. 44 - Prob. 46GPCh. 44 - Prob. 47GPCh. 44 - Prob. 48GPCh. 44 - Prob. 49GPCh. 44 - Prob. 50GPCh. 44 - Calculate the Schwarzschild radius using a...Ch. 44 - How large would the Sun be if its density equaled...Ch. 44 - Prob. 53GPCh. 44 - (a) Use special relativity and Newtons law of...Ch. 44 - Prob. 55GPCh. 44 - Prob. 56GPCh. 44 - Prob. 57GPCh. 44 - Prob. 58GP
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- I asked the following question and was given the attached solution: Suppose that the universe were full of spherical objects, each of mass m and radius r . If the objects were distributed uniformly throughout the universe, what number density (#/m3) of spherical objects would be required to make the density equal to the critical density of our Universe? Values: m = 4 kg r = 0.0407 m Answer must be in scientific notation and include zero decimal places (1 sig fig --- e.g., 1234 should be written as 1*10^3) I don't follow the work and I got the wrong answer, so please help and show your work as I do not follow along easily thanksarrow_forwardSuppose that the universe were full of spherical objects, each of mass m and radius r . If the objects were distributed uniformly throughout the universe, what number density (#/m3) of spherical objects would be required to make the density equal to the critical density of our Universe? Values: m = 10 kg r = 0.0399 m Answer must be in scientific notation and include zero decimal places (1 sig fig --- e.g., 1234 should be written as 1*10^3)arrow_forward(a) Calculate the approximate age of the universe from the average value of the Hubble constant, H0 = 20km/s ⋅ Mly . To do this, calculate the time itwould take to travel 1 Mly at a constant expansion rate of 20 km/s.(b) If deceleration is taken into account, would the actual age of the universe be greater or less than that found here? Explain.arrow_forward
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