PHYSICS F./SCI... W/MOD V.II W/KIT
4th Edition
ISBN: 9780134819884
Author: GIANCOLI
Publisher: PEARSON
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Question
Chapter 44, Problem 36P
(a)
To determine
The average density of the baryonic matter.
(b)
To determine
The density of the dark matter in the universe.
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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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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
- Assume the average density of the universe is 0.1 of the critical density needed for closure. What is the average number of protons per cubic meter, assuming the universe is composed mostly of hydrogen?arrow_forwardThe critical mass density needed to just halt the expansion of the universe is approximately (a) Convert this to (b) Find the number of neutrinos per cubic meter needed to close the universe if their average mass is and they have negligible kinetic energies.arrow_forwardI 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_forward
- b) The cosmic microwave background dates to a time when the universe was ~380,000 years old, or to a z = 1100. The blackbody temperature then was -3,000 K. Show that today the CMB temperature should be 2.725 K.arrow_forwardConsider a universe where Big Bang nucleosynthesis produced significantly more 4He than 1H. Estimate the observed redshift, z, of the Cosmic Radiation Background (CMB) by an observer that observes the CMB to have a blackbody temperature of 2.715 K. Assume this universe has Ob = 0. 0486, QDM = O. 2588 and QA = 0. 6911arrow_forwardDoes the universe have a center? Explain.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 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.arrow_forwardExplain what is meant by the term cosmological redshift, and contrast it with the Doppler shift that is observed when a luminous object recedes from an observer. From the defi- nition of redshift in terms of the observed and emitted wavelengths of photons, obtain an expression that relates redshift to the expansion factor of the Universe. Hence calculate the expansion factor of the Universe while a photon travels from a galaxy with redshift z = 1.arrow_forwardI:28) What was the density of energy released of fusing 25% of all the hydrogen in the universe into helium, at time when T = 10^9 K. Express your answer in J/m^3.arrow_forward
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