Exam 17: Supermassive Black Holes and Active Galaxies

A) Closed and open universes expand forever.
B) Closed universes expand and then contract.
C) Only flat universes expand forever.
D) Flat and open universes expand and then contract.
E) Only flat universes expand and then contract.

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A) is homogenously distributed through the Universe
B) began clumping due to tiny variations in density at the moment of the Big Bang
C) began clumping due to large variations in the distribution of matter and antimatter
D) is isotropically distributed through the Universe
E) began clumping due to the variations in the distribution of baryonic matter

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A) was faster in the early Universe when galaxies were close to each other, and has decelerated thereafter
B) was slower in the early Universe when galaxies were close to each other, and has accelerated thereafter
C) has been constant throughout the lifetime of the Universe
D) steadily accelerated from the Big Bang to the present day
E) steadily decelerated from the Big Bang to the present day

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A) high-energy photons
B) protons and antiprotons
C) protons, neutrons, electrons, and positrons (anti-electrons)
D) electrons, and positrons (anti-electrons)
E) protons, neutrons, electrons

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cosmic mic...

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A) shorter wavelength energy that has been redshifted by expansion
B) longer wavelength energy that has been redshifted by expansion
C) microwave radiation that has not been affected by expansion
D) shorter wavelength energy that has been blueshifted by expansion
E) longer wavelength energy that has been blueshifted by expansion

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A) gas has traveled with galaxies as they formed and is spread through the Universe of the present day
B) Big Bang occurred everywhere at once, and should be visible in any direction at long look-back times
C) B ig Bang occurred in a certain location, and the radiation from the gas is concentrated there
D) gas has travelled to the edges of the Universe and will be visible at negative redshifts
E) radiation emitted by the gas has travelled at the same speed as the expanding Universe and is visible all around us

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A) 0 K
B) 273 K
C) 27 K
D) 7.2 K
E) 2.7 K

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A) baryonic matter being greater than the effects of dark matter and dark energy
B) baryonic matter and dark energy being greater than the effect of dark matter.
C) dark matter and dark energy being greater than the effect of baryonic matter.
D) baryonic matter and dark matter being greater than the effect of dark energy.
E) dark matter being greater than the effect of dark energy.

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A) one second
B) one minute
C) one hour
D) one day
E) one year

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A) clumping of dark matter in the early Universe causing clumping of normal matter
B) clumping of normal matter in the early Universe causing clumping of dark matter
C) simultaneous clumping of normal and dark matter
D) large variations in the intensity of the cosmic microwave background
E) homogenous expansion of normal and dark matter

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