Astronomy Fall Semester Exam Review 2022 Flashcards
1
Q
It takes approximately ___________ for Earth to rotate once on its axis.
A
24 hours
2
Q
It takes the Earth approximately ________ to travel around the sun once.
A
365 days
3
Q
The Earth’s orbit around the Sun is in the shape of an ___________.
A
Ellipse
4
Q
During which season is Earth closest to the Sun?
A
Winter
5
Q
The Earth’s axis is tilted ________ degrees.
A
23.5
6
Q
_________ occur twice a year, when the tilt of the Earth’s axis is oriented directly towards or away from the Sun, causing the Sun to appear to reach its northernmost and southernmost extremes.
A
Solstices
7
Q
The northern hemisphere experiences the fewest daylight hours on ___________.
A
December 21
8
Q
During the summer solstice, sunlight strikes the Earth most directly at the ____________.
A
Tropic of Cancer
9
Q
How many hours of daylight does Earth experience during the vernal equinox?
A
Approximately 12
10
Q
During the winter solstice, the ____________ experiences 24 hours of daylight.
A
South Pole
11
Q
The principal culture that transferred Greek astronomical knowledge to Renaissance Europe was:
A
Islamic
12
Q
The most accurate Greek attempt to explain planetary motion was the model of:
A
Ptolemy
13
Q
The greatest contribution of the Greeks to modern thought was:
A
The development of scientific inquiry and model building
14
Q
On which of these assumptions do Ptolemy and Copernicus agree?
A
All orbits must be perfect circles
15
Q
According to Copernicus, the retrograde motion for Mars must occur:
A
at opposition, when the Earth overtakes Mars and passes between Mars and the Sun
16
Q
Which was a contribution to astronomy made by Copernicus?
A
He laid out the order and relative motion of the known solar system.
17
Q
Which of these observations of Galileo refuted Ptolemy’s epicycles?
A
the complete cycles of Venus’ phases
18
Q
A fatal flaw with Ptolemy’s model is its inability to predict the observed phases of
A
Mercury and Venus
19
Q
Kepler’s first law worked, where Copernicus’ original heliocentric model failed, because Kepler described the orbits as:
A
Elliptical, not circular
20
Q
The most famous prehistoric astronomical observatory is:
A
Stonehenge
21
Q
What contribution to astronomy was made by Tycho Brache?
A
His observations of planetary motion with great accuracy proved circular orbits could not work.
22
Q
According to Kepler’s third law, the square of the planet’s period in years is:
A
proportional to the cube of its semi-major axis in A.U.
23
Q
What does Kepler’s third law imply about planetary motion?
A
Planets further from the Sun orbit at a slower speed than planets closer to the Sun.
24
Q
Today we rely largely on what technique to precisely measure distances in the solar system?
A
Radar echo timings
25
The Law of Universal Gravitation was developed by:
Newton
26
The force of gravity between two objects:
increases with the masses of the bodies, but decreases with the square of the distances between them.
27
Kepler's second law implies what about planetary motion?
A planet moves faster when it is closer to the Sun.
28
The number of waves passing the observer per second is:
the frequency in Hertz
29
Both sound waves and electromagnetic radiation:
transfer energy
30
What does the phenomenon of diffraction demonstrate?
the wave nature of light
31
Which of these is constant for ALL types of electromagnetic radiation in a vacuum?
Velocity
32
Electromagnetic radiation:
can behave both as a wave and a particle
33
Of all the forms of electromagnetic radiation, the one with the lowest frequency is:
Radio waves
34
Colors appear different to us because of their photons' different:
frequencies
35
Which type of radiation can be observed well from Earth's surface?
Visible
36
The wavelength at which a blackbody radiated most depends on its:
Temperature
37
What is spectroscopy?
An analysis of the way in which atoms absorb and emit light
38
Typical stellar spectra appear as:
a rainbow, but with some dark lines mixed in
39
The three laws dealing with the creation of various spectra are due to:
Kirchhoff
40
An incandescent light (glowing tungsten filament) procedures:
a continuous spectrum, with the peak giving the temperature of the filament
41
An emission spectrum can be used to identify an:
atom
42
In Bohr's model of the atom, electrons:
only make transitions between orbitals of specific energies
43
A heavy neutral atom, such as iron, produces many spectral lines compared to light elements like hydrogen and helium. Why?
Because of the larger number of electrons and corresponding energy levels, more transitions are possible
44
Why are molecular lines more complex than elemental spectral lines?
Molecules can vibrate and rotate as well
45
The observed spectral lines of a star are all shifted towards the red end of the spectrum. Which statement is true?
This is an example of the Doppler Effect
46
Which of the following is the largest distance?
The orbit of the Earth around the Sun
47
Which of the following objects is furthest away from the Sun?
Mars
48
Which of the following is a star?
The Sun
49
Which of the following is the largest?
The universe
50
Which of the following are considered to be clues to how the solar system was formed?
All the planets move in the same direction around the Sun, and in the same plane.
51
Which of the following are considered to be clues to how the Milky Way was formed?
All the stars move in the same direction around the center of the galaxy and in the same plane
52
Approximately, how many stars are there in the Milky Way?
10^11
53
Approximately, how many galaxies are there in the universe?
10^11
54
Which of the following is the smallest object listed?
An atom
55
What is a nucleus made of?
Protons and neutrons
56
Which of the following lists objects from largest to smallest?
Rock - Molecule - Atom - Nucleus - Proton - Quark
57
Which of the following lists distances from shortest to longest?
Distance from the Earth to the Moon - Distances from the Earth to the Sun - Distance from the Sun to Pluto - Distance from our Sun to the nearest star
58
What model did Copernicus propose?
A model where the Sun is at the center of the universe and all objects rotate around it
59
In order for a theory to be considered a "Scientific Theory" it must have the following characteristics
Prediction - Falsifiability - Explanation
60
Which of the following is an example of evidence that showed Ptolemy's model for the universe was incomplete?
The fact that moons orbited Jupiter
61
Light can be described as a...?
Particle and a wave
62
What is the name of the light particle?
The photon
63
Which of the following lists the light from the most energetic to least energetic?
Gamma Ray - X Ray - Ultraviolet - Visible Light - Infrared - Microwaves - Radio Waves
64
Which of the following lists the wavelength of light from longest to shortest?
Radio waves - Microwaves - Infrared - Visible Light - Ultraviolet - X Ray - Gamma Rays
65
How far away is the Sun from our Earth?
8 light minutes
66
Which of the below numbers closely approximates the distance from our Sun to the nearest star?
4 light years
67
As a light source moves away from us the light will appear to be shifted to what color?
More to the red side of the spectrum
68
Christian Doppler discovered a principle which applies equally to light and sound. Which of the following choices best describes this principal?
When a source of waves if approaching an observer the wave will be "squashed up" and when the source of waves is receding from an observer the wave will be "stretched out"
69
According to Einstein's theory gravity is not a force but rather is described as....?
A consequence of the fact that space-time is not flat
70
General relativity makes predictions about what realm of the universe?
The very large (sizes bigger than people)
71
In the analogy of a rubber sheet and weighted sphere used to describe general relativity, what does the rubber sheet represent?
Space-time
72
What are the four dimensions proposed by relativity?
The three spatial dimensions (length, width, height...or x, y, z) and time
73
What is the fundamental experiment that was able to differentiate between Newton's theory of gravity and Einstein's theory of general relativity?
The experiment that tested if a star could bend the path of light
74
Which of the following interactions listed could not be correctly described with Newton's laws of gravity?
The interaction of light and stars
75
Which of the following has a bigger gravitational impact on you?
The Earth
76
What does the term "dark matter" mean?
A type of matter that does not interact much with light but whose presence can be inferred because it does influence other matter through its gravity
77
If there were no dark matter in galaxies, how should stars in a galaxy move?
A star on the outer portions of a galaxy would go around the center of the galaxy slower than a star near the center
78
Electrons are attracted to
Positively charged objects
79
What is the mediator of the electromagnetic force?
The photon
80
We can think of a force between electrically charged particles as being...?
Caused by the exchange of "virtual" photons
81
What is a consequence of the electrons orbits being quantized?
The atom can only absorb certain distinct amounts of energy corresponding to the difference in the energy levels
82
Which of the following descriptions best describes the electromagnetic force?
Electromagnetism is essentially the emission and absorption of photons carrying information
83
Why is it that we are attracted to the Earth through gravity and not electromagnetism if electromagnetism is MUCH stronger than gravity?
People and the Earth are electrically neutral
84
How many quarks are there inside the proton?
Three quarks
85
What is the particle that is the mediator of the strong force?
The gluon
86
What is the significance of the observation of spectral lines in a spectrometer attached to telescopes looking at the stars?
This observation provides us with evidence that the stars and our Sun are made up of the same elements thus are sun is not unique
87
What is the most common type of atom in the Sun?
Hydrogen
88
What characteristics determine what type of isotope an atom is?
The number of protons and neutrons
89
The sensation of being "hot" can be described from the atomic perspective as...
Many atoms are colliding with you transferring a lot of energy to you
90
If a bunch of atoms are in thermal equilibrium, then this means that:
They all roughly have the same energy
91
If a gas is in thermal equilibrium and the volume its contained in expands, we expect the temperature of the gas to
Decrease
92
Which can best describe the data that Hubble observed?
The light from distance galaxies is red-shifted
93
What can we conclude from the observed fact that light from distant galaxies appears to be red-shifted?
All distant galaxies seem to be moving away from us
94
Which of the following statements describes Hubble's findings about the distant galaxies?
He discovered that the speed at which distant galaxies move away from us increases roughly in proportion to their increasing distance from us
95
Which of the following statements describes the data about galaxies?
There appear to be the same number of galaxies in all directions
96
How old does the data predict the universe to be?
13.5 billion years old
97
Where does science say the big bang occurred?
The big bang describes an explosion which occurred simultaneously everywhere filling all space with every particle of matter rushing away from one another and thus does not have a center
98
The cosmological principle means that:
The idea that the universe looks essentially the same to everyone, everywhere in the universe
99
We currently think that the center of the universe is:
Essentially nonexistent, because the universe expands like a balloon (of which we are on the surface of) with no real center
100
The current understanding of why objects appear to be moving faster the father they are away from us is currently thought to be because:
Because space itself is expanding, and thus the further apart two points are, the faster they appear to be moving relative to each other.
101
An important piece of evidence that the universe is expanding comes from:
The wavelength of any ray of light that comes to us from a distant galaxy simply increases in proportion to the distance to that galaxy as the universe expands
102
What is the temperature of the cosmic background radiation?
2.7 Kelvin
103
The measurement that the universe looks the same in all directions is thought to be the consequence of what property of the early universe?
The fact that it passed through a state of thermal equilibrium
104
Most of the heavy elements in our universe were produced by:
Stars
105
The photons in the cosmic background radiation today are mostly:
Microwaves
106
Most of the atoms in the universe are hydrogen. The rest are mostly:
Helium
107
Photons always break up which of the following?
It depends on the energy of the photon
108
Photons in cosmic background radiation are low energy today because
The universe is expanding which stretches their wavelength
109
Which of the following constellations is not seen during the summer months in the Northern Hemisphere?
Orion
110
What northern star can be used to find your latitude in the Norther Hemisphere?
Polaris
111
Groupings of stars in the sky that are easy to recognize and have been given names are known as:
Constellations
112
What group of stars can be used as a star clock to tell time at night?
The Big Dipper
113
Stars that are close to the celestial poles, are up all night and do not rise or set, are called:
Circumpolar
114
The Sun, Moon, and planets are always found within a band of constellations known as:
Zodiac
115
In which part of the sky is the Big Dipper found?
North
116
In the Northern Hemisphere the constellation Orion is best seen in:
The winter
117
Which of the following is a constellation of zodiac?
Sagittarius
118
How does elevation of the North Star change as you move from equator to the North Pole?
Increases
119
Many great minds worked on the problem of determining longitude. Which of the following was the first to solve this problem?
John Harrison
120
Which of the following was a key constellation for navigating the Southern Hemisphere?
Southern Cross
