21st Century Astronomy
6th Edition
ISBN: 9780393428063
Author: Kay
Publisher: NORTON
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Question
Chapter 21.1, Problem 21.1CYU
To determine
The meaning of isotropy and homogeneity of universe in astronomy.
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Students have asked these similar questions
The main reason the night sky is dark is that the universe is
a.
homogeneous.
b.
static.
c.
infinite in size.
d.
expanding.
e.
finite in age.
The age of the universe can be determined if
a.
the universe is flat.
b.
the amount of dark matter in the universe can be accurately determined.
c.
the rate of recession of the galaxies in the Local Group can be accurately determined.
d.
the temperature of the cosmic background radiation can be accurately determined.
e.
the Hubble constant and density of the universe can be accurately determined.
The assumption of isotropy states that
a.
the universe looks the same at all epochs.
b.
the universe looks the same from all locations over sufficiently great distances.
c.
the universe looks the same in all directions over sufficiently great distances.
d.
all of the above are true.
e.
none of the above are true.
Chapter 21 Solutions
21st Century Astronomy
Ch. 21.1 - Prob. 21.1CYUCh. 21.2 - Prob. 21.2CYUCh. 21.3 - Prob. 21.3ACYUCh. 21.3 - Prob. 21.3BCYUCh. 21.4 - Prob. 21.4CYUCh. 21 - Prob. 1QPCh. 21 - Prob. 2QPCh. 21 - Prob. 3QPCh. 21 - Prob. 4QPCh. 21 - Prob. 5QP
Ch. 21 - Prob. 6QPCh. 21 - Prob. 7QPCh. 21 - Prob. 8QPCh. 21 - Prob. 9QPCh. 21 - Prob. 10QPCh. 21 - Prob. 11QPCh. 21 - Prob. 12QPCh. 21 - Prob. 13QPCh. 21 - Prob. 14QPCh. 21 - Prob. 15QPCh. 21 - Prob. 16QPCh. 21 - Prob. 17QPCh. 21 - Prob. 18QPCh. 21 - Prob. 19QPCh. 21 - Prob. 20QPCh. 21 - Prob. 21QPCh. 21 - Prob. 23QPCh. 21 - Prob. 24QPCh. 21 - Prob. 25QPCh. 21 - Prob. 26QPCh. 21 - Prob. 27QPCh. 21 - Prob. 28QPCh. 21 - Prob. 29QPCh. 21 - Prob. 30QPCh. 21 - Prob. 31QPCh. 21 - Prob. 32QPCh. 21 - Prob. 33QPCh. 21 - Prob. 34QPCh. 21 - Prob. 35QPCh. 21 - Prob. 36QPCh. 21 - Prob. 37QPCh. 21 - Prob. 38QPCh. 21 - Prob. 39QPCh. 21 - Prob. 40QPCh. 21 - Prob. 41QPCh. 21 - Prob. 42QPCh. 21 - Prob. 43QPCh. 21 - Prob. 44QPCh. 21 - Prob. 45QP
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- How does the age of the universe relate to the Hubble constant? a. The smaller the constant, the older the universe. b. The larger the constant, the older the universe. c. The Hubble constant is the age of the universe. d. The Hubble constant is the square of the universe. e. It is impossible to tell the age of the universe from the Hubble constant.arrow_forwardWhat is the approximate temperature of the universe that we currently observe? a. 0 K b. 2.7 K c. 273 K d. 3000 K e. 6000 Karrow_forwardWe know that dark matter must exist in galaxies. If not, many of the stars in a galaxy would ... a.Expand and go supernova due to the expansion of the Universe b.Fly away from the galaxy because the stars’ velocities are so large, and the galaxy would not have enough gravity to hold onto them c.Orbit the center of the galaxy normally d.Spiral in toward the center of the galaxy because most of the galaxy’s mass would be toward the centerarrow_forward
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