Understanding Our Universe
3rd Edition
ISBN: 9780393614428
Author: PALEN, Stacy, Kay, Laura, Blumenthal, George (george Ray)
Publisher: W.w. Norton & Company,
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Question
Chapter 15, Problem 37QAP
(a)
To determine
The plots on the given figure; does this show amount of mass present at that radius; the reason for increase in mass with the increase in radius.
(b)
To determine
The radius at which same enclosed mass of dark matter as normal matter.
(c)
To determine
The result of increasing the graph to the given radius on the blue line.
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1.2
1.0
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0.6
Cosmic background
data from COBE
0.4
0.2
0.0
0.5
10
Wavelength A in mm
c)
Background (CMB) undertaken by the COBE satellite. Use this diagram to estimate the
current temperature of the CMB. Based on your estimate, what would the temperature of
the CMB have been at a redshift of z = 5000?
The left hand diagram above shows the results from observations of the Cosmic Microwave
Radiated Intensity per Unit Wavelength
(16° Watts/m per mm)
Indicate whether the following statements are true or false.
(Select T-True, F-False. If the first is T and the rest F, enter
TFFFFF).
A) If we find an O type star in our galaxy, it must be in the disk.
B) The nearest large spiral Galaxy, similar in size to the Milky Way, is the Andromeda Galaxy (M31). It is located about 2 million light years from Earth.
C) The disk of the Milky Way galaxy is about 100,000 light years in diameter.
D) On very large scales, matter in the Universe is distributed in clumps and voids.
E) Distances to most stars in the Milky Way are measured by parallax.
F) RR Lyrae and Cepheid variable stars are used to measure the distance to nearby galaxies.
The Andromeda Galaxy, M31, is the closest large spiral galaxy to our Milky Way. When we look at its chemical spectrum, we see that its hydrogen alpha emission line (Hα) has an observed wavelength of λobs = 655 nm.-Calculate z, being careful with the sign.-How fast is it moving in km/s?-Is it redshifted or blueshifted? Is it moving towards or away from us?
answer to three significant figures.
Chapter 15 Solutions
Understanding Our Universe
Ch. 15.1 - Prob. 15.1CYUCh. 15.2 - Prob. 15.2CYUCh. 15.3 - Prob. 15.3CYUCh. 15.4 - Prob. 15.4CYUCh. 15 - Prob. 1QAPCh. 15 - Prob. 2QAPCh. 15 - Prob. 3QAPCh. 15 - Prob. 4QAPCh. 15 - Prob. 5QAPCh. 15 - Prob. 6QAP
Ch. 15 - Prob. 7QAPCh. 15 - Prob. 8QAPCh. 15 - Prob. 9QAPCh. 15 - Prob. 10QAPCh. 15 - Prob. 11QAPCh. 15 - Prob. 12QAPCh. 15 - Prob. 13QAPCh. 15 - Prob. 14QAPCh. 15 - Prob. 15QAPCh. 15 - Prob. 16QAPCh. 15 - Prob. 17QAPCh. 15 - Prob. 18QAPCh. 15 - Prob. 19QAPCh. 15 - Prob. 20QAPCh. 15 - Prob. 21QAPCh. 15 - Prob. 22QAPCh. 15 - Prob. 23QAPCh. 15 - Prob. 24QAPCh. 15 - Prob. 25QAPCh. 15 - Prob. 26QAPCh. 15 - Prob. 27QAPCh. 15 - Prob. 28QAPCh. 15 - Prob. 29QAPCh. 15 - Prob. 30QAPCh. 15 - Prob. 31QAPCh. 15 - Prob. 32QAPCh. 15 - Prob. 33QAPCh. 15 - Prob. 34QAPCh. 15 - Prob. 35QAPCh. 15 - Prob. 36QAPCh. 15 - Prob. 37QAPCh. 15 - Prob. 38QAPCh. 15 - Prob. 39QAPCh. 15 - Prob. 40QAPCh. 15 - Prob. 41QAPCh. 15 - Prob. 42QAPCh. 15 - Prob. 43QAPCh. 15 - Prob. 44QAPCh. 15 - Prob. 45QAP
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