Astro 10 Exam 3 UPDATED ACTUAL Exam
Questions and CORRECT Answers
Compared to the Sun, most other stars in the Milky Way Galaxy are
a) as small relative to the Sun as they appear in the sky.
b) smaller.
c) about the same size.
d) much larger. - CORRECT ANSWER - b) smaller.
The Sun's luminosity comes primarily from
a) chemical burning.
b) the mechanical energy of turbulence.
c) nuclear fusion.
d) gravitational contraction.
e) all of the above are comparable in importance. - CORRECT ANSWER - c) nuclear
fusion.
The energy emitted by the Sun is produced
a) in a very small region at the very center of the Sun.
b) uniformly throughout the whole Sun.
c) throughout the whole Sun, but more in the center than at the surface, as 1/r^2.
d) from radioactive elements created in the Big Bang. - CORRECT ANSWER - a) in a
very small region at the very center of the Sun.
The photosphere (the visible surface) of the Sun is like
a) the surface of the Earth; you could stand on it, if you could survive the heat.
b) the surface of the ocean; you couldn't stand on it, but you would clearly be able to detect
differences above and below it.
,c) an apparent surface; you would notice very little change as you go through it, as when you fly
through a cloud.
d) the surface of a trampoline; you could land on it, but the intense pressure would push you
away again. - CORRECT ANSWER - c) an apparent surface; you would notice very little
change as you go through it, as when you fly through a cloud.
Sunspots appear dark because they are
a) holes in the photosphere through which you can see deeply into the stellar interior.
b) a bit cooler and thus dimmer than the rest of the photosphere.
c) large opaque structures that block light from the glowing solar surface.
d) causing retinal damage. - CORRECT ANSWER - b) a bit cooler and thus dimmer than
the rest of the photosphere.
The 11 year solar cycle is NOT followed by the
a) number of sunspots on the Sun.
b) typical latitude of sunspots on the Sun.
c) rate of solar flares.
d) incidence of strong aurora on the Earth.
e) None of the above. - CORRECT ANSWER - e) None of the above.
The chemical composition of the Sun 3 billion years ago was different from what it is now in that
it had
a) more hydrogen.
b) more helium.
c) more nitrogen.
d) molecular hydrogen. - CORRECT ANSWER - a) more hydrogen.
Inside a star the mass of our Sun, energy is transported from the deep interior out toward the
surface by a process most like the process that
a) makes a blacktop hot in the summertime.
,b) heats the coil on an electric stove.
c) makes hot water boil.
d) makes your hand feel heat when you put it near a candle flame. - CORRECT
ANSWER - d) makes your hand feel heat when you put it near a candle flame.
The temperature in and around the Sun
a) drops continuously as you move outward
b) rises continuously as you move outward
c) drops as you move from the center to the photosphere, then rises above the photosphere
d) drops as you move from the center to the photosphere, then rises above the photosphere -
CORRECT ANSWER - c) drops as you move from the center to the photosphere, then
rises above the photosphere
The light from the east limb (edge) of the Sun is blueshifted and the light from the west limb is
redshifted. This is because
a) different kinds of atoms emit light at the opposite edges.
b) the Sun is rotating.
c) the distance from the Sun to the Earth changes.
d) the two sides of the Sun are at different temperatures. - CORRECT ANSWER - b) the
Sun is rotating.
The energy of a photon emitted by thermonuclear processes in the core of the Sun takes
thousands or even millions of years to emerge from the surface because
a) it is circling in the gravitational field of the Sun.
b) it loses energy due to convection, conduction, and radiation.
c) of the Sun's enormous radius.
d) it is absorbed and re-emitted countless times along the way. - CORRECT ANSWER -
d) it is absorbed and re-emitted countless times along the way.
If the center of the Sun could be heated slightly, the nuclear reactions would occur faster and
hence release more heat, so the Sun's core would
, a) collapse.
b) expand and hence cool back to its previous temperature.
c) expand and hence heat up even more.
d) explode. - CORRECT ANSWER - b) expand and hence cool back to its previous
temperature.
Tremendous pressure is created at the Sun's center due to its own gravity. The Sun is kept from
collapsing by
a) neutrinos and other particles generated by nuclear fusion.
b) a hard inner core.
c) thermal (gas) pressure generated by nuclear fusion.
d) thermal (gas) pressure left over from the formation of the Sun. - CORRECT
ANSWER - c) thermal (gas) pressure generated by nuclear fusion.
Stars are
a) solid.
b) liquid.
c) gaseous.
d) mostly carbon, oxygen, nitrogen, and iron.
e) both c and d. - CORRECT ANSWER - c) gaseous.
If the Sun were the size of a tennis ball (6.35 cm in diameter) then the red giant star Betelgeuse
would have a diameter of
a) 2.3 cm, about the size of a ping pong ball.
b) 23 cm, about the size of a basketball.
c) 23 m, larger than the equivalent size of Mars' orbit.
d) 23 km. - CORRECT ANSWER - c) 23 m, larger than the equivalent size of Mars' orbit.
Most of the brightest stars in the sky are
Questions and CORRECT Answers
Compared to the Sun, most other stars in the Milky Way Galaxy are
a) as small relative to the Sun as they appear in the sky.
b) smaller.
c) about the same size.
d) much larger. - CORRECT ANSWER - b) smaller.
The Sun's luminosity comes primarily from
a) chemical burning.
b) the mechanical energy of turbulence.
c) nuclear fusion.
d) gravitational contraction.
e) all of the above are comparable in importance. - CORRECT ANSWER - c) nuclear
fusion.
The energy emitted by the Sun is produced
a) in a very small region at the very center of the Sun.
b) uniformly throughout the whole Sun.
c) throughout the whole Sun, but more in the center than at the surface, as 1/r^2.
d) from radioactive elements created in the Big Bang. - CORRECT ANSWER - a) in a
very small region at the very center of the Sun.
The photosphere (the visible surface) of the Sun is like
a) the surface of the Earth; you could stand on it, if you could survive the heat.
b) the surface of the ocean; you couldn't stand on it, but you would clearly be able to detect
differences above and below it.
,c) an apparent surface; you would notice very little change as you go through it, as when you fly
through a cloud.
d) the surface of a trampoline; you could land on it, but the intense pressure would push you
away again. - CORRECT ANSWER - c) an apparent surface; you would notice very little
change as you go through it, as when you fly through a cloud.
Sunspots appear dark because they are
a) holes in the photosphere through which you can see deeply into the stellar interior.
b) a bit cooler and thus dimmer than the rest of the photosphere.
c) large opaque structures that block light from the glowing solar surface.
d) causing retinal damage. - CORRECT ANSWER - b) a bit cooler and thus dimmer than
the rest of the photosphere.
The 11 year solar cycle is NOT followed by the
a) number of sunspots on the Sun.
b) typical latitude of sunspots on the Sun.
c) rate of solar flares.
d) incidence of strong aurora on the Earth.
e) None of the above. - CORRECT ANSWER - e) None of the above.
The chemical composition of the Sun 3 billion years ago was different from what it is now in that
it had
a) more hydrogen.
b) more helium.
c) more nitrogen.
d) molecular hydrogen. - CORRECT ANSWER - a) more hydrogen.
Inside a star the mass of our Sun, energy is transported from the deep interior out toward the
surface by a process most like the process that
a) makes a blacktop hot in the summertime.
,b) heats the coil on an electric stove.
c) makes hot water boil.
d) makes your hand feel heat when you put it near a candle flame. - CORRECT
ANSWER - d) makes your hand feel heat when you put it near a candle flame.
The temperature in and around the Sun
a) drops continuously as you move outward
b) rises continuously as you move outward
c) drops as you move from the center to the photosphere, then rises above the photosphere
d) drops as you move from the center to the photosphere, then rises above the photosphere -
CORRECT ANSWER - c) drops as you move from the center to the photosphere, then
rises above the photosphere
The light from the east limb (edge) of the Sun is blueshifted and the light from the west limb is
redshifted. This is because
a) different kinds of atoms emit light at the opposite edges.
b) the Sun is rotating.
c) the distance from the Sun to the Earth changes.
d) the two sides of the Sun are at different temperatures. - CORRECT ANSWER - b) the
Sun is rotating.
The energy of a photon emitted by thermonuclear processes in the core of the Sun takes
thousands or even millions of years to emerge from the surface because
a) it is circling in the gravitational field of the Sun.
b) it loses energy due to convection, conduction, and radiation.
c) of the Sun's enormous radius.
d) it is absorbed and re-emitted countless times along the way. - CORRECT ANSWER -
d) it is absorbed and re-emitted countless times along the way.
If the center of the Sun could be heated slightly, the nuclear reactions would occur faster and
hence release more heat, so the Sun's core would
, a) collapse.
b) expand and hence cool back to its previous temperature.
c) expand and hence heat up even more.
d) explode. - CORRECT ANSWER - b) expand and hence cool back to its previous
temperature.
Tremendous pressure is created at the Sun's center due to its own gravity. The Sun is kept from
collapsing by
a) neutrinos and other particles generated by nuclear fusion.
b) a hard inner core.
c) thermal (gas) pressure generated by nuclear fusion.
d) thermal (gas) pressure left over from the formation of the Sun. - CORRECT
ANSWER - c) thermal (gas) pressure generated by nuclear fusion.
Stars are
a) solid.
b) liquid.
c) gaseous.
d) mostly carbon, oxygen, nitrogen, and iron.
e) both c and d. - CORRECT ANSWER - c) gaseous.
If the Sun were the size of a tennis ball (6.35 cm in diameter) then the red giant star Betelgeuse
would have a diameter of
a) 2.3 cm, about the size of a ping pong ball.
b) 23 cm, about the size of a basketball.
c) 23 m, larger than the equivalent size of Mars' orbit.
d) 23 km. - CORRECT ANSWER - c) 23 m, larger than the equivalent size of Mars' orbit.
Most of the brightest stars in the sky are
