Big Bang and Cosmology Exam Review answers

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Big Bang and Cosmology Exam Review
1) One light year is about 9.5x1012 Km
2) What does the red shift tell us about the motion of
the universe? It is expanding
3) What is currently the most accepted theory about
the origin of the universe called? Big Bang
4) What can I tell about a star based on its color?
What elements are present
5) What is the most common unit for measuring the
distance of cosmic objects? Light Years
6) Who first proposed that the universe is expanding
and what made him think so? Edwin Hubble,
distant objects were redder than they should have
been.
7) Which cosmic objects are moving faster, the near
or the far? The farther away they are the faster
they are moving
8) What is the difference between a hypothesis and a
theory? A theory has been thoroughly tested,
attempts to explain, and is generally accepted
9) True or False: Although you spent all of
elementary school learning that being a tattle tale
wasn't acceptable, it is precisely what you are
supposed to be in a lab setting. True
10) Who first proposed the dual nature of light?
Einstein
11) Name one experiment that 'proves' light is a
particle. Photoelectric effect
12) Name one experiment that 'proves' light is a
wave. Double slit experiment
13) What are the two competing theories that
describe the fate of the universe? Big Freeze and
the Big Crunch
14) Which one does the scientific community
generally regard as most likely, given what we
currently know? Big Freeze (dark energy > dark
matter)
15) What was the first of the four fundamental forces
to emerge from the big bang? Gravity
16) How would I define the unit light year? And why is
it a measure of distance, not time? It is the
distance light travels in a year. D = v * t
17) What other forms of electromagnetic radiation
join visible light in the electromagnetic spectrum?
Radio, micro, infrared, ultraviolet, x-rays, &
gamma
18) What is the Doppler effect and how does it relate
to astronomy? The observed frequency is effected
by the relative motion of the source and observer
19) True or false the big bang produced more antimatter than matter? False. more matter than antimatter
20) What crazy-small unit of time do cosmologists use
when speaking about the fractions of a second
immediately after the big bang? Planck time
21) How does an atom become ionized? Gaining or
losing electrons
22) What are spectral emission lines? Specific and
unique frequencies of EMR given off by an
element or molecule
23) What are absorption lines? Specific and unique
frequencies of light absorbed by a substance
(usually a gas) leaving gaps in the spectrum
24) Which has more energy, a photon of a radio wave
or a photon of a gamma wave? Gamma wave
25) Which moves faster a microwave or an infrared
wave? Same speed
26) Why do different elements have different colors of
characteristic light? It takes different amounts of
energy to move their electrons to different energy
levels
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