Question 1

All black holes have the same amount of gravitational force.

Accepted Answer

A) True 
 B)False

Question 2

The term "Schwarzschild radius" refers to

Accepted Answer

A)  the distance to which gas is ejected in a planetary nebula. 
B)  half the diameter of a neutron star. 
C)  half the diameter of the singularity in a black hole. 
D)  the distance from the center of a black hole at which the escape velocity becomes equal to the speed of light.

Question 3

X-rays that come from the vicinity of a black hole actually originate from

Accepted Answer

A)  well inside the event horizon. 
B)  its exact center,or singularity. 
C)  relatively far away from the black hole,where matter is still relatively cool. 
D)  just outside the event horizon,on the accretion disk.

Question 4

In a binary star system,an unseen component is found to have a mass of about 8 solar masses.If this were a normal star,then it would be visible,so it must be a collapsed object.Theoretical considerations tell us that it must be a

Accepted Answer

A)  white dwarf. 
B)  black hole. 
C)  neutron star. 
D)  brown dwarf.

Question 5

What is believed to be the mass of the black hole candidate Cygnus X-1?

Accepted Answer

A)  30 solar masses 
B)  1 billion solar masses 
C)  7 solar masses 
D)  1 solar mass

Question 6

At what location in the space around a black hole does the escape velocity become equal to the speed of light?

Accepted Answer

A)  At the point where escaping X-rays are produced 
B)  At the point where clocks are observed to slow down by a factor of 2 
C)  At the event horizon 
D)  At the singularity

Question 7

A Type Ia supernova is thought to result from the thermonuclear explosion of a white dwarf star in a close binary system with a larger companion star.

Accepted Answer

A) True 
 B)False

Question 8

A neutron star is a stellar corpse supported by

Accepted Answer

A)  electron degeneracy pressure. 
B)  neutron degeneracy pressure. 
C)  black hole pressure. 
D)  None of these

Question 9

When a star becomes a black hole,its gravitational pull becomes stronger.

Accepted Answer

A) True 
 B)False

Question 10

A neutron star will be detected from Earth as a pulsar by its regular radio pulses ONLY if Earth lies

Accepted Answer

A)  in the plane of the neutron star's magnetic equator,halfway between its magnetic poles. 
B)  almost directly in line with the magnetic axis of the neutron star at some time during the star's rotation. 
C)  directly above the rotation axis of the rotating neutron star. 
D)  in the neutron star's "equator," the plane perpendicular to its spin axis.

Question 11

What is the difference between a stellar black hole and a supermassive black hole?

Accepted Answer

The answer of What is the difference between a stellar...

Question 12

Ancient Chinese astronomers recorded the appearance of what phenomenon in 1054 A.D.?

Accepted Answer

A)  A nearby nova explosion in a nearby galaxy 
B)  A brilliant auroral display covering the whole Earth 
C)  A supernova,visible in daylight,within our Galaxy 
D)  A bright binary star undergoing eclipse

Question 13

The diameter of the black hole candidate Cygnus X-1 has been estimated by

Accepted Answer

A)  combining the amount of energy received at Earth per second with the distance to the source to estimate the total energy emitted per second. 
B)  measuring how quickly it flickers in intensity. 
C)  measuring how long it takes to block off the light from its companion star during an eclipse (i.e. ,as it passes in front of its companion star as seen from Earth). 
D)  combining its distance with its angular diameter to find its physical size.

Question 14

How does the diameter of a black hole (size of the event horizon)depend on the mass inside the black hole?

Accepted Answer

A)  The greater the mass,the smaller the diameter. 
B)  The greater the mass,the greater the diameter up to the mass limit for a black hole;above that mass,the black hole collapses. 
C)  The diameter does not depend on the mass. 
D)  The greater the mass,the greater the diameter.

Question 15

In general,a Type Ia supernova is brighter than a Type II supernova.

Accepted Answer

A) True 
 B)False

Question 16

What is actually located at the event horizon of a black hole,to define this entity?

Accepted Answer

A)  An infinitely dense concentration of mass 
B)  A magnetic field of immense strength 
C)  A sphere of photons 
D)  Nothing

Question 17

If,by definition,no light can escape from a black hole,how are they detected?

Accepted Answer

The answer of If,by definition,no light can escape from a...

Question 18

Every year,two or three supernovae are seen within our own Galaxy.

Accepted Answer

A) True 
 B)False

Question 19

What is the event horizon in relationship to black holes?

Accepted Answer

The answer of What is the event horizon in relationship...

Question 20

A pulsar is a(n)

Accepted Answer

A)  interstellar beacon manufactured by little green persons (LGPs). 
B)  type of variable star,pulsating rapidly in size and brightness. 
C)  rapidly spinning neutron star. 
D)  accretion disk around a black hole,emitting light as matter is accumulated on the disk.

Exam 12: Predicting the Violent End of the Largest Stars

All black holes have the same amount of gravitational force.

The term "Schwarzschild radius" refers to

X-rays that come from the vicinity of a black hole actually originate from

In a binary star system,an unseen component is found to have a mass of about 8 solar masses.If this were a normal star,then it would be visible,so it must be a collapsed object.Theoretical considerations tell us that it must be a

What is believed to be the mass of the black hole candidate Cygnus X-1?

At what location in the space around a black hole does the escape velocity become equal to the speed of light?

A Type Ia supernova is thought to result from the thermonuclear explosion of a white dwarf star in a close binary system with a larger companion star.

A neutron star is a stellar corpse supported by

When a star becomes a black hole,its gravitational pull becomes stronger.

A neutron star will be detected from Earth as a pulsar by its regular radio pulses ONLY if Earth lies

What is the difference between a stellar black hole and a supermassive black hole?

Ancient Chinese astronomers recorded the appearance of what phenomenon in 1054 A.D.?

The diameter of the black hole candidate Cygnus X-1 has been estimated by

How does the diameter of a black hole (size of the event horizon) depend on the mass inside the black hole?

In general,a Type Ia supernova is brighter than a Type II supernova.

What is actually located at the event horizon of a black hole,to define this entity?

If,by definition,no light can escape from a black hole,how are they detected?

Every year,two or three supernovae are seen within our own Galaxy.

What is the event horizon in relationship to black holes?

A pulsar is a(n)