Question :
1.As a star exhausts hydrogen in its core, it A.becomes : 1777244
1.As a star exhausts hydrogen in its core, it
A.becomes hotter and more luminous
B.becomes hotter and less luminous
C.becomes cooler and less luminous
D.becomes larger in radius and hotter
2.A star will experience a helium flash if
A.it is less massive than about 3 solar masses
B.its has become a red giant star
C.its has formed a helium core
D.the material in the core has gradually become degenerate
E.All of the above must be true.
3.In degenerate matter
A.pressure depends only on the temperature.
B.temperature depends only on density.
C.pressure does not depend on temperature.
D.pressure does not depend on density.
E.b and c
4.Giant and supergiant stars are rare because
A.they do not form as often as main sequence stars.
B.the star blows up before the giant or supergiant stage is reached
C.the giant or supergiant stage is very short.
D.the giant or supergaint stage is very long
5.A(n) ____ is a collection of 100 to 1000 stars in a region about 25 pc in diameter. The stars in the collection are typically quite young.
A.Herbig Haro object
B.globular cluster
C.open cluster
D.giant cluster
E.supernova
6.A(n) ____ is a collection of 105 to 106 stars in a region 10 to 30 pc in diameter. The stars in the collection tend to be more than 109 years old and mostly yellow and red stars.
A.Herbig Haro object
B.globular cluster
C.open cluster
D.giant cluster
E.supernova
7.Stars within a cluster that are at the turnoff point
A.have life expectancies that are equal to the age of the cluster.
B.are stars that are just becoming white dwarfs.
C.are stars that are just entering the main sequence portion of their evolution.
D.are stars that are about to supernova.
E.are stars that are generally spectral type G stars.
8.In star clusters, the ____ stars are giant stars fusing helium in their cores and then in their shells.
A.turnoff point
B.main sequence
C.turnon point
D.hydrogen flash
E.horizontal branch
9.The ____________ are places in the orbital plane of a binary star system where a bit of matter can reach stability. The one located directly between the two stars is the point where the Roche lobes meet.
A.turnoff points
B.horizontal branch
C.Lagrangian points
D.synchrotron points
E.radiation belts
10.A mass is transferred through the inner Langragria point in a binary system toward a white dwarf, the material forms a rapidly growing whirlpool of material known as a(n)
A.accretion disk.
B.Lagrangian point.
C.Algol paradox.
D.planetary nebula.
E.supernova remnant.
