what happens to a star as it exhausts hydrogen in its core?
MULTIPLE CHOICE. �Cull the one alternative that best completes the statement or answers the question.
i) �Which two energy sources can assist a star maintain its internal thermal pressure?
A) nuclear fusion and gravitational wrinkle
B) nuclear fission and gravitational wrinkle
C) nuclear fusion and nuclear fission
D) chemical reactions and gravitational contraction
E) nuclear fusion and chemical reactions
2) �What happens when a star exhausts its cadre hydrogen supply?
A) Its core contracts, but its outer layers expand and the star becomes bigger and brighter.
B) It contracts, becoming smaller and dimmer.
C) It contracts, becoming hotter and brighter.
D) It expands, condign bigger but dimmer.
E) Its core contracts, but its outer layers aggrandize and the star becomes bigger but cooler and therefore remains at the same brightness.
three) �What is a planetary nebula?
A) a deejay of gas surrounding a protostar that may course into planets
B) what is left of the planets around a star after a depression-mass star has ended its life
C) the expanding shell of gas that is no longer gravitationally held to the remnant of a low-mass star
D) the molecular cloud from which protostars class
E) the expanding beat of gas that is left when a white dwarf explodes as a supernova
4) �On a Hertzsprung\'2DRussell diagram, where on the principal sequence would nosotros observe stars that take the greatest mass?
A) upper right B) �lower right C) �upper left D) �lower left
5) �Which element has the lowest mass per nuclear particle and therefore cannot release energy by either fusion or fission?
A) hydrogen B) �oxygen C) �silicon D) �iron �East) �uranium
6) �On a Hertzsprung\'2DRussell diagram, where would we find stars that are cool and dim?
A) upper right B) �lower right C) �upper left D) �lower left
7) �What type of star is our Sun?
A) low-mass star
B) intermediate-mass star
C) loftier-mass star
eight) �Which of the following best describes the axes of a Hertzsprung\'2DRussell (H\'2DR) diagram?
A) surface temperature on the horizontal axis and luminosity on the vertical axis
B) mass on the horizontal axis and luminosity on the vertical centrality
C) surface temperature on the horizontal axis and radius on the vertical axis
D) mass on the horizontal centrality and stellar age on the vertical centrality
E) interior temperature on the horizontal axis and mass on the vertical axis
9) �Why are neutrinos so difficult to notice?
A) because in that location are so rare
B) considering they have no mass
C) because they movement at, or close to, the speed of light
D) because they rarely collaborate with matter
E) We don't know: this is the essence of the solar neutrino problem.
10) �A star of spectral blazon G lives approximately how long on the primary sequence?
A) 1,000 years
B) 10,000 years
C) 1 million years
D) 100 million years
E) 10 billion years
xi) �From the eye outward, which of the following lists the "layers" of the Sun in the correct lodge?
A) core, radiations zone, convection zone, corona, chromosphere, photosphere
B) core, corona, radiation zone, convection zone, photosphere, chromosphere
C) core, radiations zone, convection zone, photosphere, chromosphere, corona
D) core, convection zone, radiation zone, corona, chromosphere, photosphere
E) cadre, convection zone, radiation zone, photosphere, chromosphere, corona
12) �How do man-built nuclear power plants on Earth generate energy?
A) chemical reactions
B) nuclear fusion
C) nuclear fission
D) converting kinetic energy into electricity
Eastward) converting gravitational potential free energy into electricity
13) �The core of the Sun is
A) at the aforementioned temperature and density every bit the surface.
B) at the aforementioned temperature just denser than the surface.
C) hotter and denser than the surface.
D) constantly rising to the surface through convection.
Due east) composed of fe.
14) �What do we mean when we say that the Sun is in gravitational equilibrium?
A) The hydrogen gas in the Sun is balanced so that it never rises up or falls downwardly.
B) The Dominicus maintains a steady temperature.
C) This is some other way of stating that the Dominicus generates energy by nuclear fusion.
D) There is a balance within the Sun between the outward button of pressure level and the inward pull of gravity.
East) The Sun e'er has the same amount of mass, creating the aforementioned gravitational force.
fifteen) �Cluster ages tin be determined from
A) chief sequence fitting.
B) principal sequence turnoff.
C) pulsating variable stars.
D) spectroscopic binaries.
E) visual binaries.
xvi) �Since all stars begin their lives with the same bones composition, what characteristic virtually determines how they will differ?
A) location where they are formed
B) time they are formed
C) luminosity they are formed with
D) mass they are formed with
East) colour they are formed with
17) �Compared to the star it evolved from, a ruby giant is
A) hotter and brighter.
B) hotter and dimmer.
C) cooler and brighter.
D) cooler and dimmer.
Due east) the aforementioned temperature and effulgence.
18) �Studies of sunquakes, or helioseismology, have revealed that
A) the Sun vibrates simply on the surface.
B) "sunquakes" are caused by similar processes that create earthquakes on the Earth.
C) the Lord's day generates energy by nuclear fusion.
D) our mathematical models of the solar interior are fairly accurate.
East) neutrinos from the solar core achieve the solar surface easily.
19) �On a Hertzsprung\'2DRussell diagram, where would nosotros find stars that are cool and luminous?
A) upper correct B) �lower right C) �upper left D) �lower left
20) �A star's luminosity is the
A) apparent brightness of the star in our sky.
B) surface temperature of the star.
C) lifetime of the star.
D) total amount of lite that the star will radiate over its entire lifetime.
E) full corporeality of low-cal that the star radiates each second.
21) �What are the appropriate units for the Sun'due south luminosity?
A) watts B) �joules C) �meters D) �Newtons E) �kilograms
22) �On a Hertzsprung\'2DRussell diagram, where would nosotros find white dwarfs?
A) upper right B) �lower right C) �upper left D) �lower left
23) �The helium fusion process results in the production of
A) hydrogen. B) �oxygen. C) �carbon. D) �nitrogen. E) �iron.
24) �Which is closest to the temperature of the cadre of the Sun?
A) 10,000 K
B) 100,000 Grand
C) i million K
D) 10 1000000 G
E) 100 million 1000
25) �The spectral sequence in order of decreasing temperature is
A) OFBAGKM.
B) OBAGFKM.
C) OBAFGKM.
D) ABFGKMO.
E) BAGFKMO.
26) �Compared to the star information technology evolved from, a white dwarf is
A) hotter and brighter.
B) hotter and dimmer.
C) cooler and brighter.
D) libation and dimmer.
Eastward) the aforementioned temperature and brightness.
27) �Why does a star grow larger afterward information technology exhausts its core hydrogen?
A) The outer layers of the star are no longer gravitationally attracted to the core.
B) Hydrogen fusion in a shell outside the core generates enough thermal pressure to push the upper layers outward.
C) Helium fusion in the core generates plenty thermal pressure to push the upper layers outward.
D) Helium fusion in a shell outside the core generates enough thermal pressure to push the upper layers outward.
Eastward) The internal radiation generated past the hydrogen fusion in the core has heated the outer layers enough that they can expand after the star is no longer fusing hydrogen.
28) �What processes are involved in the sunspot cycle?
A) gravitational contraction of the Sun
B) wave motions in the solar interior
C) variations of the solar thermostat
D) the winding of magnetic field lines due to differential rotation
29) �What happens to the cadre of a star after a planetary nebula occurs?
A) It contracts from a protostar to a main-sequence star.
B) It breaks apart in a violent explosion.
C) It becomes a white dwarf.
D) It becomes a neutron star.
E) none of the above
30) �What is the average temperature of the surface of the Sun?
A) 1 meg Chiliad B) �100,000 K C) �x,000 K D) �6,000 K E) �1,000 1000
31) �Which layer of the Lord's day practise we unremarkably see?
A) photosphere
B) corona
C) chromosphere
D) convection zone
E) radiation zone
32) �The phase of matter in the Sunday is
A) gas.
B) plasma.
C) liquid.
D) solid.
E) a mixture of all of the above.
33) �Suppose you put two protons near each other. Because of the electromagnetic forcefulness, the two protons will
A) collide.
B) �remain stationary.
C) attract each other.
D) repel each other.
E) join together to form a nucleus.
34) �What happens when the gravity of a massive star is able to overcome neutron degeneracy pressure?
A) The cadre contracts and becomes a white dwarf.
B) The core contracts and becomes a ball of neutrons.
C) The core contracts and becomes a blackness hole.
D) The star explodes violently, leaving nothing behind.
Due east) Gravity is not able to overcome neutron degeneracy pressure level.
35) �How does the Sun generate energy today?
A) nuclear fission
B) nuclear fusion
C) chemical reactions
D) gravitational contraction
E) gradually expanding in size
36) �If the altitude betwixt us and a star is doubled, with everything else remaining the same, the luminosity
A) is decreased by a cistron of four, and the apparent brightness is decreased by a factor of iv.
B) is decreased by a factor of two, and the apparent effulgence is decreased past a factor of 2.
C) remains the same, but the apparent effulgence is decreased by a factor of two.
D) the luminosity remains the aforementioned, just the apparent brightness is decreased past a cistron of four.
E) is decreased by a factor of four, only the apparent effulgence remains the aforementioned.
37) �Sunspots are cooler than the surrounding solar surface because
A) they are regions where convection carries cooler material down.
B) strong magnetic fields slow convection and forbid hot plasma from entering the region.
C) magnetic fields trap ionized gases that absorb low-cal.
D) there is less fusion occurring in that location.
E) magnetic fields lift material from the surface of the Sun, cooling off the material faster.
38) �Later a supernova event, what is left behind?
A) e'er a white dwarf
B) ever a neutron star
C) ever a black hole
D) either a white dwarf or a neutron star
Due east) either a neutron star or a black hole
39) �Which of the post-obit sequences correctly describes the stages of life for
a depression-mass star?
A) red giant, protostar, chief-sequence, white dwarf
B) white dwarf, master-sequence, cherry-red giant, protostar
C) protostar, red giant, main-sequence, white dwarf
D) protostar, main-sequence, white dwarf, red giant
E) protostar, primary-sequence, carmine giant, white dwarf
xl) �Which event marks the beginning of a supernova?
A) the onset of helium burning after a helium flash in a star with mass comparable to that of the Sun
B) the sudden outpouring of X rays from a newly formed accretion disk
C) the sudden collapse of an iron core into a meaty ball of neutrons
D) the beginning of neon burning in an extremely massive star
E) the expansion of a low-mass star into a red giant
The following questions refer to the sketch below of an H-R diagram for a star cluster.
Figure 14.ii
41) �Consider the star to which the arrow points. Which of the post-obit statements nearly this star is not true?
A) It is significantly less massive than the Sun.
B) Information technology is larger in radius than the Sunday.
C) It is brighter than the Sun.
D) Its surface temperature is lower than the Sunday'southward.
E) Its core temperature is higher than the Dominicus'southward.
ane) �Answer: �A
2) �Answer: �A
3) �Answer: �C
four) �Answer: �C
5) �Answer: �D
6) �Answer: �B
vii) �Reply: �A
8) �Answer: �A
9) �Respond: �D
10) �Answer: �Due east
11) �Answer: �C
12) �Respond: �C
13) �Answer: �C
14) �Answer: �D
xv) �Reply: �B
sixteen) �Answer: �D
17) �Respond: �C
18) �Answer: �D
19) �Respond: �A
xx) �Answer: �East
21) �Answer: �A
22) �Answer: �D
23) �Answer: �C
24) �Answer: �D
25) �Answer: �C
26) �Answer: �B
27) �Answer: �B
28) �Answer: �D
29) �Answer: �C
thirty) �Answer: �D
31) �Answer: �A
32) �Answer: �B
33) �Answer: �D
34) �Answer: �C
35) �Respond: �B
36) �Answer: �D
37) �Respond: �B
38) �Answer: �Eastward
39) �Reply: �E
40) �Reply: �C
41) �Answer: �A
Source: http://www.physics.sfasu.edu/friedfeld/ast105/AST105_Exam3.htm
0 Response to "what happens to a star as it exhausts hydrogen in its core?"
Post a Comment