1 | Page
Astronomy 101 Midterm Exam Questions
and Correct Answers
Suppose you are in an elevator that is traveling upward at
constant speed. How does your weight compare to your normal
weight on the ground? Ans: It is the same.
Suppose you have a 100-watt light bulb that you leave turned on
for one minute. How much energy does it use? Ans: 6,000 joules.
Which of the following conditions lead you to see an absorption
line spectrum from a cloud of gas in interstellar space? Ans: The
cloud is cool and lies between you and a hot star.
Why are astronauts weightless in the Space Station? Ans: The
Space Station is constantly in free-fall around the Earth.
Gamma rays have a very small ______. Ans: wavelength
Which of the following is not a major reason why astronomers
would like an observatory on the far side of the Moon? Ans:
Telescopes on the Moon could see objects in all parts of the sky
equally well, whereas telescopes on Earth can see only portions of
the sky that depend on their latitude.
Which of the following represents a case in which you are not
accelerating? Ans: Driving in a straight line at 60 miles per hour.
Suppose the planet Uranus were much brighter in the sky, so that
it was as easily visible to the naked eye as Jupiter or Saturn. What
would most likely be true in that case? Ans: A week would have
eight days instead of seven.
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, 2 | Page
Which of the following has your "cosmic address" in the correct
order? Ans: You, Earth, solar system, Milky Way Galaxy, Local
Group, Local Supercluster, universe.
A net force acting on an object will always cause a change in the
object's _________. Ans: momentum
Imagine another solar system, with a star more massive than the
Sun. Suppose a planet with the same mass as Earth orbits at a
distance of 1 AU from the star. How would the planet's year
(orbital period) compare to Earth's year? Ans: The planet's year
would be shorter than Earth's.
Which planet has the most extreme seasons? Ans: Uranus
What is true about Scientific Theory? Ans: A scientific theory
cannot be accepted until it has been proven true beyond all doubt.
Suppose you kick a soccer ball straight up to a height of 10
meters. Which of the following is true about the gravitational
potential energy of the ball during its flight? Ans: The ball's
gravitational potential energy is greatest at the instant when the
ball is at its highest point.
When we look at an object that is 1,000 light-years away we see it
_________. Ans: as it was 1,000 years ago
Which of the following telescopes would benefit most from
adaptive optics? Ans: The Keck I telescope on Mauna Kea.
Which of the following is not consistent with the major hallmarks
of science? Ans: Science consists of proven theories that are
understood to be true explanations of reality.
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How did the Ptolemaic model explain the apparent retrograde
motion of the planets? Ans: The planets moved along small circles
that moved on larger circles around the Earth.
Suppose you use the Southern Cross to determine that the south
celestial pole appears 40 degrees above your horizon. Then you
must be located at _________. Ans: latitude 40 degrees south
What is not true about motion in the universe? Ans: The
mysterious dark matter is the fastest-moving material in the
universe.
The angular separation of two stars is 0.1 arcseconds and you
photograph them with a telescope that has an angular resolution
of 1 arcsecond. What will you see? Ans: The photo will seem to
show only one star rather than two.
Venus has a higher average surface temperature than Mercury.
Why? Ans: Because its surface is heated by an extreme greenhouse
effect.
You observe a full moon rising at sunset. What will you see at
midnight? Ans: A full moon high in the sky.
Which of the following best describes why we say that light is an
electromagnetic wave? Ans: The passage of a light wave can cause
electrically charged particles to move up and down.
The Andromeda Galaxy is faintly visible to the naked eye in the
constellation Andromeda. Suppose instead it were located in the
same direction in space as the center of the Milky Way Galaxy (but
still at its current distance). How would it appear to the eye in that
case? Ans: We could not see it at all.
© 2025 All rights reserved
Astronomy 101 Midterm Exam Questions
and Correct Answers
Suppose you are in an elevator that is traveling upward at
constant speed. How does your weight compare to your normal
weight on the ground? Ans: It is the same.
Suppose you have a 100-watt light bulb that you leave turned on
for one minute. How much energy does it use? Ans: 6,000 joules.
Which of the following conditions lead you to see an absorption
line spectrum from a cloud of gas in interstellar space? Ans: The
cloud is cool and lies between you and a hot star.
Why are astronauts weightless in the Space Station? Ans: The
Space Station is constantly in free-fall around the Earth.
Gamma rays have a very small ______. Ans: wavelength
Which of the following is not a major reason why astronomers
would like an observatory on the far side of the Moon? Ans:
Telescopes on the Moon could see objects in all parts of the sky
equally well, whereas telescopes on Earth can see only portions of
the sky that depend on their latitude.
Which of the following represents a case in which you are not
accelerating? Ans: Driving in a straight line at 60 miles per hour.
Suppose the planet Uranus were much brighter in the sky, so that
it was as easily visible to the naked eye as Jupiter or Saturn. What
would most likely be true in that case? Ans: A week would have
eight days instead of seven.
© 2025 All rights reserved
, 2 | Page
Which of the following has your "cosmic address" in the correct
order? Ans: You, Earth, solar system, Milky Way Galaxy, Local
Group, Local Supercluster, universe.
A net force acting on an object will always cause a change in the
object's _________. Ans: momentum
Imagine another solar system, with a star more massive than the
Sun. Suppose a planet with the same mass as Earth orbits at a
distance of 1 AU from the star. How would the planet's year
(orbital period) compare to Earth's year? Ans: The planet's year
would be shorter than Earth's.
Which planet has the most extreme seasons? Ans: Uranus
What is true about Scientific Theory? Ans: A scientific theory
cannot be accepted until it has been proven true beyond all doubt.
Suppose you kick a soccer ball straight up to a height of 10
meters. Which of the following is true about the gravitational
potential energy of the ball during its flight? Ans: The ball's
gravitational potential energy is greatest at the instant when the
ball is at its highest point.
When we look at an object that is 1,000 light-years away we see it
_________. Ans: as it was 1,000 years ago
Which of the following telescopes would benefit most from
adaptive optics? Ans: The Keck I telescope on Mauna Kea.
Which of the following is not consistent with the major hallmarks
of science? Ans: Science consists of proven theories that are
understood to be true explanations of reality.
© 2025 All rights reserved
, 3 | Page
How did the Ptolemaic model explain the apparent retrograde
motion of the planets? Ans: The planets moved along small circles
that moved on larger circles around the Earth.
Suppose you use the Southern Cross to determine that the south
celestial pole appears 40 degrees above your horizon. Then you
must be located at _________. Ans: latitude 40 degrees south
What is not true about motion in the universe? Ans: The
mysterious dark matter is the fastest-moving material in the
universe.
The angular separation of two stars is 0.1 arcseconds and you
photograph them with a telescope that has an angular resolution
of 1 arcsecond. What will you see? Ans: The photo will seem to
show only one star rather than two.
Venus has a higher average surface temperature than Mercury.
Why? Ans: Because its surface is heated by an extreme greenhouse
effect.
You observe a full moon rising at sunset. What will you see at
midnight? Ans: A full moon high in the sky.
Which of the following best describes why we say that light is an
electromagnetic wave? Ans: The passage of a light wave can cause
electrically charged particles to move up and down.
The Andromeda Galaxy is faintly visible to the naked eye in the
constellation Andromeda. Suppose instead it were located in the
same direction in space as the center of the Milky Way Galaxy (but
still at its current distance). How would it appear to the eye in that
case? Ans: We could not see it at all.
© 2025 All rights reserved
