Seminar assignments - Bonus quiz PDF

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Bonus Quiz...

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Section 1 1. What important molecules of life did Miller and Urey brew up?



lean acids



antacids



RNA



amino acids (Correct)



fatty acids

2. The best answer to both the flatness and horizon problems is



the Steady State Theory.



decoupling.



the inflationary epoch. (Correct)



dark energy.



the GUT theory.

3. About 15 minutes after the Big Bang the composition of the Universe was



only helium.



all elements found in nature now.



only hydrogen.



all elements up to iron.



hydrogen and helium, but very little else. (Correct)

4. Before the decoupling,



the universe was opaque to radiation. (Correct)



protons and electrons combined to form atoms.



there was more helium than hydrogen.



the universe was transparent to radiation.



deuterium produced electrons and positrons.

5. With a Hubble constant of 70 km/sec/Mpc, the critical density would be



1.4 g/cc.



6.23 × 10-23 g/mole.



3 × 10-31 g/cc.



4 × 10-36 g/cc.



9 × 10-27 kg/m3. (Correct)

6. In the critical density universe now proposed, the ratio of dark energy to matter is about



1 to 100.



1 to 5.



1 to 1.



10 to 1.



3 to 1. (Correct)

7. Like dark matter, dark energy will also retard the expansion of the universe.



True



False (Correct)

8. The tiny ripples in the background radiation COBE found are due to



different velocities of the edge of the universe.



a gravitational redshift caused by growing dark clumps. (Correct)



reddening by interstellar dust clouds in our galaxy.



bubble-like nature of space.



variations in the speed of different wavelengths of light.

9. Concerning dark energy, we do know



that it was revealed with Type II supernovae distances in the late 1990s.



that it makes up 90% of all the matter and energy in the whole universe.



combined with dark matter, it will ultimately produce a closed universe.





its density remains constant over time, so it is not important in the early universe. (Correct) that it is created when matter annihilates anti-matter.

10. If the density of the universe is greater than critical, then



the universe is flat, and Euclid is right.



there is more matter than energy.



the universe will end up as nothing but black holes.



the universe is closed, gravity wins, and will shrink to the Big Crunch. (Correct)



the universe will continue expanding forever.

11. In a closed universe, if you could send out a powerful enough light, it would eventually return from behind you.



True (Correct)



False

12. How does the energy of the cosmic microwave background compare to the energy radiated by all the stars and galaxies that ever existed?



27% cosmic background, 73% starlight



The starlight now dominates the background, as your eyes show clearly.



They are equal.



about ten times more from the Big Bang than from stars and galaxies (Correct)



We have no way of comparing matter and energy this way.

13. How long between the evolution of single versus multicellular organisms?



63 million years



one billion years



600 million years



4.5 billion years



2.5 billion years (Correct)

14. The definition of "life" requires only that an entity be able to reproduce itself.



True



False (Correct)

15. Studies from ________ led to the discovery of "dark energy."



the COBE microwave ripples



the gravitational lensing by MACHOs



Type I supernovae at very large red shifts (Correct)



Type II supernovae in the Large Magellanic Cloud



Cepheid variables in the Virgo Cluster

16. Deuterium abundance suggests that normal matter makes up only 3-4% of the critical density.



True (Correct)



False

17. What temperature has the Big Bang cooled to by now?



5,800 K



about 3,000 K



just over 2.7 K (Correct)



about 300 K



1.4 K

18. Most of the deuterium formed right after the Big Bang



turned into dark matter.



did nothing and all of it is still around today.



broke down into electrons and neutrons.



was found in the globular clusters.



quickly burned into helium nuclei. (Correct)

19. Which type of molecules, vital to our life, were found to have survived a fiery descent to Earth on meteorites?



amino acids (Correct)



vitamins



lipids



sugars



DNA

20. The presently accepted value of the Hubble constant gives an age of



14 billion years. (Correct)



8-9 billion years.



22 billion years.



4.5 billion years.



18 billion years.

21. If Ωo is less than one, then



no matter could have existed.



only dark energy exists in the universe.



the universe is closed, and must recycle.



there is more matter than energy in the universe.



the universe will expand forever. (Correct)

22. In which of the following models will the universe stop expanding and collapse back on itself?



closed universe



critical density universe (Incorrect)



open universe



steady state universe



All have an ultimate collapse.

23. The expansion rate of the universe is



constant.



increasing. (Correct)



independent of time.



different in different directions.



decreasing.

24. The redshift of the galaxies is correctly interpreted as



the differences in temperatures and star formation in old and young galaxies.



placing our Galaxy near the center of the Local Group.



a Doppler shift due to the random motions of galaxies in space.



an aging of light as gravity weakens with time.



space itself is expanding with time, so the photons are stretched while they travel through space. (Correct)

25. What key event happened during the decoupling epoch?



Pairs of neutrons and protons were created.



Electrons and positrons were created.



The universe underwent a brief period of very rapid expansion.





Expansion cooled the universe enough that protons could capture electrons in orbit. (Correct) Dark energy accelerated the cosmos on to infinity...