Question 1

Compared to a clock on the surface of the Earth,a clock on the International Space Station runs:

Accepted Answer

A) at approximately the same rate,but slightly slower. 
B) significantly slower 
C) significantly faster 
D) sometimes faster,sometimes slower 
E) at an equal rate,except during eclipses 
A) at approximately the same rate,but slightly slower. 
B) significantly slower 
C) significantly faster 
D) sometimes faster,sometimes slower 
E) at an equal rate,except during eclipses

Question 2

The Earth orbits the Sun because the Sun changes space around it but not time.

Accepted Answer

A) True 
 B)False

Question 3

Muons are elementary particles that decay into other particles in about 2 microseconds.They are formed in the upper atmosphere of the Earth from high energy cosmic rays,and can be detected on the ground even though they could only travel a few hundred meters before decaying according to Newtonian physics.How does relativity explain how we can detect them on the ground? Explain both in our reference frame and in the frame of the muon.

Accepted Answer

From our reference frame,we see the muon

Question 4

A black hole can be produced if the stellar core left over after a supernova is larger than 3 M⨀.

Accepted Answer

A) True 
 B)False

Question 5

Gamma-ray bursts are likely to be:

Accepted Answer

A) the signs of accretion onto black holes 
B) the product of merging neutron stars 
C) produced by the most energetic supernova explosions 
D) the result of neutron stars accreting mass and turning into black holes 
E) produced by intelligent life in the universe exploding nuclear bombs 
A) the signs of accretion onto black holes 
B) the product of merging neutron stars 
C) produced by the most energetic supernova explosions 
D) the result of neutron stars accreting mass and turning into black holes 
E) produced by intelligent life in the universe exploding nuclear bombs

Question 6

What is the meaning of the word spacetime?

Accepted Answer

A) It is a mental framework for keeping track of numbers in Newtonian physics. 
B) Space and time form a two-dimensional region where physics takes place. 
C) The term has no special meaning;it's just a fancy way to sound important when talking about physics. 
D) It is the combined treatment of space and time in the theory of relativity. 
E) It is the idea that observers will always measure the same locations and times of events. 
A) It is a mental framework for keeping track of numbers in Newtonian physics. 
B) Space and time form a two-dimensional region where physics takes place. 
C) The term has no special meaning;it's just a fancy way to sound important when talking about physics. 
D) It is the combined treatment of space and time in the theory of relativity. 
E) It is the idea that observers will always measure the same locations and times of events.

Question 7

Hawking radiation from black holes refers to:

Accepted Answer

A) light emitted from matter falling onto a black hole 
B) the gravitational redshift of light emitted near the event horizon 
C) the radiation of particles created near the event horizon 
D) high-energy X-rays and gamma rays from the formation of a black hole 
E) the optical and infrared light from an energetic supernova explosion 
A) light emitted from matter falling onto a black hole 
B) the gravitational redshift of light emitted near the event horizon 
C) the radiation of particles created near the event horizon 
D) high-energy X-rays and gamma rays from the formation of a black hole 
E) the optical and infrared light from an energetic supernova explosion

Question 8

What is the meaning of the phrase inertial frame of reference?

Accepted Answer

A) a reference frame that is not accelerating 
B) a reference frame that is stationary with respect to the Earth 
C) a reference frame that is in motion at constant speed 
D) a reference frame that is accelerating at a constant rate 
E) a reference frame in which there are strong gravitational forces 
A) a reference frame that is not accelerating 
B) a reference frame that is stationary with respect to the Earth 
C) a reference frame that is in motion at constant speed 
D) a reference frame that is accelerating at a constant rate 
E) a reference frame in which there are strong gravitational forces

Question 9

The equivalence principle says that:

Accepted Answer

A) the universe is homogeneous and isotropic 
B) being stationary in a gravitational field is the same as being in an accelerated reference frame 
C) at any radius inside a star the outward gas pressure must balance the weight of the material on top 
D) mass and energy are interchangeable and neither can be destroyed 
E) gravity does not exist in space 
A) the universe is homogeneous and isotropic 
B) being stationary in a gravitational field is the same as being in an accelerated reference frame 
C) at any radius inside a star the outward gas pressure must balance the weight of the material on top 
D) mass and energy are interchangeable and neither can be destroyed 
E) gravity does not exist in space

Question 10

The Schwarzschild radius of a 10M⨀ is __________ the size of the Schwarzschild radius of a 5 M⨀ black hole.

Accepted Answer

A) 1/5 
B) 1/2 
C) equal to 
D) 2 times 
E) 5 times 
A) 1/5 
B) 1/2 
C) equal to 
D) 2 times 
E) 5 times

Question 11

You observe a distant galaxy apparently moving away at 1/3 the speed of light (v c/3).If you could measure the speed that this galaxy's light is passing the Earth,you would get:

Accepted Answer

A) c/3 
B) 2c/3 
C) c 
D) 4c/3 
E) 5c/3 
A) c/3 
B) 2c/3 
C) c 
D) 4c/3 
E) 5c/3

Question 12

One consequence of Einstein's ideas about the speed of light is that:

Accepted Answer

A) if two events take place at the same time,all observers will see that event simultaneously 
B) whether events are seen as simultaneous or not depends on the motion of an observer 
C) observers will always disagree on when an event took place 
D) it is not possible to know when an event happened 
E) moving observers can always know whether they are in motion 
A) if two events take place at the same time,all observers will see that event simultaneously 
B) whether events are seen as simultaneous or not depends on the motion of an observer 
C) observers will always disagree on when an event took place 
D) it is not possible to know when an event happened 
E) moving observers can always know whether they are in motion

Question 13

When do the predictions of special relativity match those of Newtonian physics?

Accepted Answer

A) in terrestrial laboratories 
B) inside our Solar System 
C) when different observers are at rest with one another 
D) when objects have a low mass 
E) when objects are moving slowly 
A) in terrestrial laboratories 
B) inside our Solar System 
C) when different observers are at rest with one another 
D) when objects have a low mass 
E) when objects are moving slowly

Question 14

__________ is the result of mass distorting the fabric of spacetime.

Accepted Answer

A) Energy 
B) Radiation 
C) Fusion 
D) Gravity 
E) Electric charge 
A) Energy 
B) Radiation 
C) Fusion 
D) Gravity 
E) Electric charge

Question 15

What is the meaning of the equation E = mc2?

Accepted Answer

This is the famous equation relating ene

Question 16

A red giant star is found to be orbiting an unseen object with a short orbital period.By measuring the speed at which it orbits,astronomers deduce that the object has a mass of 10M⨀ This object is probably a __________ because __________.

Accepted Answer

A) black hole;the giant star is massive and could only be in orbit about something even more massive 
B) black hole;its mass is too large to be a neutron star or a white dwarf 
C) neutron star;any supernova that would have made a black hole would have destroyed the red giant 
D) M-dwarf star;only such stars would be faint enough to go unseen in this system 
E) black hole;most red giants orbit neutron stars,and neutron stars can turn into black holes 
A) black hole;the giant star is massive and could only be in orbit about something even more massive 
B) black hole;its mass is too large to be a neutron star or a white dwarf 
C) neutron star;any supernova that would have made a black hole would have destroyed the red giant 
D) M-dwarf star;only such stars would be faint enough to go unseen in this system 
E) black hole;most red giants orbit neutron stars,and neutron stars can turn into black holes

Question 17

Describe two possible ways to make a black hole.

Accepted Answer

Black holes can be made in supernova exp

Question 18

The Sun could turn into a black hole at the end of its life.

Accepted Answer

A) True 
 B)False

Question 19

If the Earth were to shrink in size until it became a black hole,its Schwarzschild radius would be:

Accepted Answer

A) 1 cm 
B) 1 m 
C) 1 km 
D) 10 km 
E) 200 km 
A) 1 cm 
B) 1 m 
C) 1 km 
D) 10 km 
E) 200 km

Question 20

Einstein's special theory of relativity implies that if a person standing at the front of a train traveling at 0.1 km/s shines a flashlight out in front of the train,the emitted photons will travel at a speed of 300,000.1 km/s.

Accepted Answer

A) True 
 B)False

Exam 18: Relativity and Black Holes

Compared to a clock on the surface of the Earth,a clock on the International Space Station runs:

The Earth orbits the Sun because the Sun changes space around it but not time.

A black hole can be produced if the stellar core left over after a supernova is larger than 3 M⨀.

Gamma-ray bursts are likely to be:

What is the meaning of the word spacetime?

Hawking radiation from black holes refers to:

What is the meaning of the phrase inertial frame of reference?

The equivalence principle says that:

The Schwarzschild radius of a 10M⨀ is __________ the size of the Schwarzschild radius of a 5 M⨀ black hole.

You observe a distant galaxy apparently moving away at 1/3 the speed of light (v c/3).If you could measure the speed that this galaxy's light is passing the Earth,you would get:

One consequence of Einstein's ideas about the speed of light is that:

When do the predictions of special relativity match those of Newtonian physics?

__________ is the result of mass distorting the fabric of spacetime.

What is the meaning of the equation E = mc2?

A red giant star is found to be orbiting an unseen object with a short orbital period.By measuring the speed at which it orbits,astronomers deduce that the object has a mass of 10M⨀ This object is probably a __________ because __________.

Describe two possible ways to make a black hole.

The Sun could turn into a black hole at the end of its life.

If the Earth were to shrink in size until it became a black hole,its Schwarzschild radius would be:

Einstein's special theory of relativity implies that if a person standing at the front of a train traveling at 0.1 km/s shines a flashlight out in front of the train,the emitted photons will travel at a speed of 300,000.1 km/s.

Why Learn Astronomy

Patterns in the Skymotions of Earth

Motion of Astronomical Bodies

Gravity and Orbits

Light

The Tools of the Astronomer

The Birth and Evolution of Planetary Systems

The Terrestrial Planets and Earths Moon

Atmospheres of the Terrestrial Planets

Worlds of Gas and Liquid the Giant Planets

Planetary Adornments Moons and Rings

Dwarf Planets and Small Solar System Bodies

Taking the Measure of Stars

Our Starthe Sun

Star Formation and the Interstellar Medium

Evolution of Low-Mass Stars

Evolution of High-Mass Stars

The Expanding Universe

Galaxies

The Milky Waya Normal Spiral Galaxy

Modern Cosmology

Large-Scale Structure in the Universe

Life

Filters

A black hole can be produced if the stellar core left over after a supernova is larger than 3 M_⨀.

The Schwarzschild radius of a 10M_⨀ is __________ the size of the Schwarzschild radius of a 5 M_⨀ black hole.

What is the meaning of the equation E = mc²?

A red giant star is found to be orbiting an unseen object with a short orbital period.By measuring the speed at which it orbits,astronomers deduce that the object has a mass of 10M_⨀ This object is probably a because .