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C. Answers to Quizzes
Lab 1:
1) Suppose you want to know how many nickels are in 17 dollars. If there are 20 nickels in 1 dollar,
then which of the following correctly formulates the solution?
2) Convert 150,000,000,000 into scientific notation
3) On a clear night the International Space Station has an angular size of about 49 arcseconds.
How big is this in radians?
4) Mars has an angular size of approximately 8.0 arcseconds and is 175,000,000 km away. Use
to figure out the diameter of Mars.
5) The International Space Station is about 90 meters across and about 380 kilometers away. One
night it appears to be the same angular size as Jupiter. Jupiter is 143,000 km in size. Use
to figure out how far away Jupiter is in AU.
Lab 2:
1) Which of the following is NOT a characteristic of electromagnetic waves?
2)
3) How many electrons does the following atom possess?
4)
5) Which of the following types of radiation has the longest wavelength?
Lab 3:
1) The term used to describe the Doppler shift in wavelength of light emitted by a star moving
away from the Earth is:
2)
blazing.
pitch as _________ that it actually is because _________.
3)
398.1 nm. How fast is the star moving and is it moving towards the Earth or away from the
Earth?
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4)
listener observe if the police car is driving towards him at 65 mph?
5) Which of the following situations will lead to a Doppler shift being observed by a participant of
the situation?
c) A woman in a speed boat races full throttle away from the dock, where a radio is playing
rock and roll.
Lab 4:
1) The solar wind originates from which part of the Sun?
2) Why are astronomers interested in the relative abundance of the various particles that make up
the solar wind?
c) All of the above
3) A proton, neutron, and electron all travel at the same speed and in the same direction; each
encounters the same uniform magnetic field. Which of these particles is deflected the most?
4)
5) Where do cosmic rays come from?
Lab 5:
1) How do we know that the interior of the Earth is less dense that the surface?
d) None of the above
2) Which of the following cannot travel through liquid?
3) Which is the correct ordering of the interior regions of the Earth, starting from the outermost?
d) crust, mantle, liquid core, solid core
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4)
5) Which of the following planets shows evidence of plate tectonics?
Lab 6:
1) Tidal forces are a result of:
2) The _____ exerts the largest gravitational force on the Earth, and the _____ exerts the largest
tidal force on the Earth.
3) When do neap tides occur?
4) A large moon orbiting a planet will likely:
5) What does the Roche limit mainly depend on?
Lab 7:
1) Whether or not a planet can retain an atmosphere primarily depends upon what?
2) A disposable tank of helium can be purchased to fill up balloons. Such tanks hold about 422
liters of helium compressed to 17.7 atm at room temperature (or 395 K), and cost about $50.
Use the ideal gas law (PV = nRT) to calculate the number of moles of Helium gas in the tank. For
these units of pressure and volume, R = 0.0821 (atm L)/(mol K).
c) 231.5 moles
3) According to the ideal gas law for a fixed amount of gas, if the _____ is constant, then when the
_____ increases the volume should _____.
4) According to the Maxwell distribution, which of these gases will have the largest average
velocity?
5) Why is a hotter planet more likely to retain an atmosphere that a cold one that is approximately
the same size and mass?
d) None of the above because a hotter planet is less likely to retain an atmosphere under these
conditions.
Lab 8:
1) What is an extrasolar planet?
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2) Why does the wobble used in the Doppler wobble method occur?
a) The wobble occurs as the planet orbits the star; it pulls the star back and forth, causing it to
3) Which of the following properties can be precisely determined solely using the Doppler wobble
method?
4) Which of the following can be approximately determined if planetary transit data is obtained for
a system that already has Doppler wobble data?
d) All of the above.
5)
a) We do not know if the systems that contain these planets are common, or if they merely
Lab 9:
1) Why is a blink comparator a good way to find asteroids and KBOs?
2)
3) Why are there Kirkwood gaps in the asteroid belt?
a) The gaps represent orbits that are unstable due to the gravitational influence of Jupiter.
4) What is albedo?
5) What assumptions do we often have to make when figuring out the individual masses of binary
asteroids or KBOs?
Lab 10:
1) Helioseismology is the science of:
2) Astronomers measure the surface vibrations by studying:
3) How do the vibrational waves in the Sun make it back up to the surface?
c) The increased temperature and density at lower depths increases the speed of the wave,
causing it to bend.
4) In general, the Standard Solar Model ________ the data obtained from helioseismology.
5) Data from helioseismology also indicates that the interior of the Sun ___________.
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Lab 11:
1) An HR diagram is a plot of:
2) A star with an apparent magnitude of 2.00 appears _____ than a star with an apparent
magnitude of 1.00.
3) For any given star, the distance modulus:
a) Is the difference between the absolute magnitude and apparent magnitude of that star.
4) Why can the age of a star cluster be determined?
5) If the stars of a cluster are plotted according to their measured apparent magnitudes and
Lab 12:
1) Visual binaries are binary systems that are detected through:
2) In a binary system, the _____ remains constant.
3) To determine the mass of each individual star in a binary system, what do we need to measure?
d) All of the above.
4) For a spectroscopic binary, astronomers determine the mass ratio using:
5) Eclipsing binaries are binary systems that are detected through:
Lab 13:
1) Approximately how big are white dwarfs?
2) Define a classical nova.
a) A classical nova is when material from a binary companion accretes onto the star, resulting
in thermonuclear runaway.
3) Type Ia supernova is:
d) All of the above.
4) Supernova nucleosythesis is the process by which:
5) What is the Chandrasekhar limiting mass?
Lab 14:
1) What are pulsars?
d) All of the above.
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2) What are neutron stars?
3) What is the current explanation of the pulses of light we observe from a pulsar?
d) Strong magnetic fields around a spinning neutron star emit continuous beams of light; the
4) – graph?
5) What interesting peculiarity came out of observing the P- graphs for pulsars?
Lab 15:
1) The bending of light due to gravity was first observed in conjunction with:
c) A solar eclipse.
2) Why are astronomers interested in binary pulsars?
a) They are an excellent way to verify the existence of gravitational waves.
3) What is the photon sphere of a black hole?
4) Which of the following distinguishing characteristics is destroyed by entry into a black hole?
5) Which of these is NOT a way in which black holes are detected?
Lab 16:
1) An astronomical unit, or AU, is defined as :
c) The average distance between Earth and the Sun.
2) A light year is set by:
3) Why is the parsec a reasonable unit of distance measurement for almost all stars?
a) Because all stars (other than the Sun) have a parallax angle of less than 1 arc second.
4) Why are Cepheid variables important to astronomy?
c) The period of pulsation of a Cepheid variable is directly related to its absolute magnitude, so
5) The distance modulus provides a means of finding the distance to an astronomical object in
terms of which of the following?
Lab 17:
1) Why do astronomers believe that dark matter exists?
2) Why are the total mass and visible mass curves similar at small distances and so different at
greater distances from the galactic center?
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3) Which type of force does dark matter interact with most strongly?
Lab 18:
1) What is the current model describing the appearance of active galaxies?
d) A supermassive rotating black hole drives massive jets of material moving at near the speed
of light.
2) How do astronomers know that the jets are created by strong magnetic fields?
3) How do the astronomers know that the jets are moving faster that the speed of light?
d) The jets only appear to be moving faster that the speed of light due to an optival illusion.
4) What evidence supports the hypothesis of a supermassive black hole at the center of the Milky
Way galaxy?
c) The orbits of stars near the center of the galaxy suggest that lots of mass are crammed into
very small regions.
5) How is the mass of the object Sagittarius A* determined?
b) rd law.
Lab 19:
1)
2)
c) The universe is expanding.
3)
4) ant?
d) All of the above.
5) Where is the center of the expansion of the Universe?
Lab 20:
1) The geometry of the universe depends on the total _____ it contains.
a) mass, energy, and pressure
2) expressed in terms of a quantity called?
3) What is the cosmological constant?
4) Although the Universe could be open, closed or flat the evidence currently available suggests
that it is:
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5) Which of the following energy densities appears to dominate our Universe at the current time?
c) Vacuum energy