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Chapter 13 Clickers
Astronomy: A Beginner’s
Guide to the Universe
Seventh Edition
Neutron Stars
and Black Holes
© 2013 Pearson Education, Inc.
Question 1
Pulsars usually show all of the following EXCEPT
a) extremely rapid rotation.
b) high-temperature fusion
reactions.
c) a narrow regular pulse of radiation.
d) high-speed motion through the
galaxy.
e) an intense magnetic field.
© 2013 Pearson Education, Inc.
Question 1
Pulsars usually show all of the following EXCEPT
a) extremely rapid rotation.
b) high-temperature fusion
reactions.
c) a narrow regular pulse of radiation.
d) high-speed motion through the
galaxy.
e) an intense magnetic field.
Explanation:
Pulsars are neutron stars no longer
undergoing fusion in their cores.
© 2013 Pearson Education, Inc.
Question 2
Many millisecond pulsars lie within
a) emission nebulae.
b) giant molecular clouds.
c) globular clusters.
d) planetary nebulae.
e) open clusters.
© 2013 Pearson Education, Inc.
Question 2
Many millisecond pulsars lie within
a) emission nebulae.
b) giant molecular clouds.
c) globular clusters.
d) planetary nebulae.
e) open clusters.
Explanation:
The cores of globular clusters are
densely packed with stars, suggesting
that millisecond pulsars might result
from “spinning up” as a result of
stellar encounters.
© 2013 Pearson Education, Inc.
The core of globular cluster 47 Tucanae
Question 3
The lighthouse model explains how
a) pulsars can be used as interstellar
navigation beacons.
b) the period of pulsation increases
as a neutron star collapses.
c) pulsars have their rotation axis
pointing toward Earth.
d) a rotating neutron star
generates an observable
beam of light.
© 2013 Pearson Education, Inc.
Question 3
The lighthouse model explains how
a) pulsars can be used as interstellar
navigation beacons.
b) the period of pulsation increases
as a neutron star collapses.
c) pulsars have their rotation axis
pointing toward Earth.
d) a rotating neutron star
generates an observable
beam of light.
© 2013 Pearson Education, Inc.
Question 4
One possible explanation for a gamma-ray burster is
a) matter spiraling into a large black hole.
b) the collision of neutron stars in a binary system.
c) variations in the magnetic fields of a pulsar.
d) repeated nova explosions.
e) All of the above are possible.
© 2013 Pearson Education, Inc.
Question 4
One possible explanation for a gamma-ray burster is
a) matter spiraling into a large black hole.
b) the collision of neutron stars in a binary system.
c) variations in the magnetic fields of a pulsar.
d) repeated nova explosions.
e) All of the above are possible.
Explanation:
Gamma-ray bursts vary in length,
and the coalescence of two neutron
stars seems to account for short bursts.
© 2013 Pearson Education, Inc.
Question 5
Cygnus X-1 is
a) NASA’s latest X-ray orbiting telescope.
b) a millisecond pulsar with three planets.
c) the strongest X-ray eclipsing binary system.
d) a likely black hole binary star system.
e) the first gamma-ray burster spotted in X rays.
© 2013 Pearson Education, Inc.
Question 5
Cygnus X-1 is
a) NASA’s latest X-ray orbiting telescope.
b) a millisecond pulsar with three planets.
c) the strongest X-ray eclipsing binary system.
d) a likely black hole binary star system.
e) the first gamma-ray burster spotted in X rays.
Explanation:
Cygnus X-1 is an X-ray source with
one visible star orbited by an unseen
companion of at least 10 solar
masses, and very rapid changes in
the signal indicating a small source.
© 2013 Pearson Education, Inc.
Question 6
The force of gravity can pull on
a) a beam of light.
b) a massive object.
c) neutrinos.
d) antimatter.
e) All of the above are correct.
© 2013 Pearson Education, Inc.
Question 6
The force of gravity can pull on
a) a beam of light.
b) a massive object.
c) neutrinos.
d) antimatter.
e) All of the above are correct.
Explanation:
Gravity is described by general relativity
as a bending of space, and all particles,
including photons, move through warped
space along curved paths.
© 2013 Pearson Education, Inc.
Question 7
If the sun was replaced by a one-solar-mass
black hole
a) Earth’s orbit would not change.
b) Earth would be pulled into the black hole.
c) X rays would destroy Earth.
d) Earth would be torn apart from the tidal force.
e) life would be unchanged.
© 2013 Pearson Education, Inc.
Question 7
If the sun was replaced by a one-solar-mass
black hole
a) Earth’s orbit would not change.
b) Earth would be pulled into the black hole.
c) X rays would destroy Earth.
d) Earth would be torn apart from the tidal force.
e) life would be unchanged.
Explanation:
The force of gravity depends only on mass and distance, not the type of
matter, or its size.
© 2013 Pearson Education, Inc.
Question 8
The event horizon of a black hole
a) is the point where X rays emerge.
b) is the physical surface of the hole.
c) defines the outer edge of an accretion disk.
d) is measured by the Schwarzschild radius.
e) extends for millions of miles into space.
© 2013 Pearson Education, Inc.
Question 8
The event horizon of a black hole
a) is the point where X rays emerge.
b) is the physical surface of the hole.
c) defines the outer edge of an accretion disk.
d) is measured by the Schwarzschild radius.
e) extends for millions of miles into space.
Explanation:
The event horizon is the surface of an
imaginary sphere around a collapsed
object inside of which nothing, including
light, can escape.
© 2013 Pearson Education, Inc.