Download Exam #1 Review

Exam #1 Review
Astronomy 103, Spring ‘09
Timbie/Schechtman-Rook
If a beam of light has a
-6
wavelength of 10 meters,
what is its frequency?
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A. 3x102 Hz.
B. 3x1014 Hz.
C. 3x10-14 Hz.
D. 3x108 Hz.
You are standing at a latitude
25o north of the equator. What
angle does the Sun make with
the southern horizon at noon
on the Summer solstice?
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A. 50o.
B. 1.5o.
C. 48.5o.
D. None of the above.
Which kind of photon has the
highest energy?
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A. Radio.
B. Visible.
C. Infrared.
D. X-ray.
The temperature of a
blackbody with λmax = 1 cm is:
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A. 0.29 K
B. 5800 K
C. 3 K
D. 0.05 K
An asteroid orbits the Sun at a
distance of 2 AU. What is its
period?
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A. 1.4 years.
B. 2.8 years.
C. 4.0 years.
D. 8.0 years.
Name all three of Kepler’s
laws:
Name two of Newton’s Laws
of motion:
Galileo used his observations
of the changing phases of
Venus to demonstrate that
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A. the Sun moves around the Earth.
B. the Earth is a sphere.
C. the Moon orbits the Earth.
D. Venus follows an orbit around the
Sun rather than the Earth.
If we measure that a certain
emission line is blue-shifted
on one side of a galaxy and
red-shifted on the other, what
do we conclude?
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A. The galaxy is moving towards us.
B. The galaxy is moving away from us.
C. The galaxy is merging.
D. The galaxy is rotating.
A sidereal day is
• A. the time it takes for a star directly
overhead to return to being directly
overhead.
• B. Measured using the Sun.
• C. Dependent on your latitude.
• D. B & C.
Which of the following is NOT
equivalent to 30 kilometers?
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A. 30,000 meters.
B. 3x106 centimeters.
C. 3x103 meters.
D. 30,000,000 millimeters.
If an object moves along a
curved path at a constant
speed, you can infer that
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A. a force is acting on it.
B. it is losing mass.
C. it is accelerating.
D. both A & C.
Two spaceships having different
masses but rocket engines of
identical force coast together through
space at constant velocity. If they fire
their rockets at the same time, which
of the two ships will speed up faster?
• A. The one with the lower mass.
• B. The one with the higher mass.
• C. They will speed up equally, because they
have identical rocket engines.
• D. They cannot speed up at all, because they
are in space.
If you double the distance
between two objects, and
double the masses of both
objects, the force of gravity
between the two
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A. Decreases by a factor of two.
B. Increases by a factor of two.
C. Stays the same.
D. None of the above.
A neon sign emits a bright red
glow because
• A. the strongest neon emission lines in the visible
part of the spectrum are around 400 nm.
• B. the strongest neon emission lines in the visible
part of the spectrum are around 700 nm.
• C. it is a blackbody with a peak wavelength around
400 nm.
• D. it is a blackbody with a peak wavelength around
700 nm.
If an object’s temperature
doubles, its total flux
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A. increases by a factor of two.
B. decreases by a factor of two.
C. increases by a factor of 16.
D. increases by a factor of four.
If the wavelength of a photon
doubles, its energy
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A. is halved.
B. doubles.
C. remains the same.
D. is quartered.
An object in orbit around the
Earth stays in orbit because
• A. the spin of the Earth propels it
outward.
• B. gravity is much weaker in space.
• C. the gravity of the other planets
balances out the Earth’s gravity.
• D. none of the above.
When a photon interacts with
an atom, what changes occur
in the atom?
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A. The atomic number increases.
B. The nucleus begins to glow.
C. An electron changes its orbital.
D. The photon becomes trapped in
orbit.
If the Sun’s declination is 0o on
March 21 of a particular year,
how long will it be before it is
at this declination again?
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A. 1 year.
B. 6 months.
C. 26,000 years.
D. Always - the declination of the Sun is
0o by definition.
The most famous person
associated with the
heliocentric model is:
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A. Aristotle.
B. Nicolaus Copernicus.
C. Leonardo Da Vinci.
D. Tycho Brahe.
3.14x10-1 + 6.86x104 is most
closely approximated by:
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A. 10x104
B. 3.72x104
C. 7.17x104
D. 6.86x104
If a [=] kg/(m*s) and b [=]
W*m2, a*b [=]
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A. W*kg/s.
B. W*m*kg/s.
C. Newtons.
D. W*kg/(m*s)
In New York City, the
constellation Orion is high in
the sky around 11 pm in
January. At what time of the
day or night would Orion be
high in the sky in July?
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A. 5 AM.
B. 11 AM.
C. 5 PM.
D. 11 PM.
Retrograde motion is:
• A. The apparent backwards motion of
the planets against the stars.
• B. Due to the orbits of the Earth and the
planets around the Sun.
• C. Explained by epicycles in the
Ptolemiac model.
• D. All of the above.
The seasons are caused by
• A. the Earth being much closer to the Sun
in the summer, and much further in the
winter.
• B. The tilt of the Earth increases the
amount of sunlight the Earth receives in
the summer.
• C. The Sun changes emits more light in
the summer than in the winter.
• D. None of the above.
Increasing the temperature of
a star _________ the peak
wavelength of its spectrum.
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A. increases
B. cancels out
C. decreases
D. does not change