Question 1

Which of the following statements about antimatter is true ?

Accepted Answer

A)  antimatter is only a theory, we have no evidence that it exists 
B)  antimatter only exists in Earth laboratories; it cannot be made in stars 
C)  antimatter cannot be made in laboratories; we have tried but it just can't be done 
D)  when a particle of matter and the corresponding particle of antimatter meet, they become pure energy 
E)  our telescopes clearly see many nearby antimatter stars in the Milky Way galaxy 
A)  antimatter is only a theory, we have no evidence that it exists 
B)  antimatter only exists in Earth laboratories; it cannot be made in stars 
C)  antimatter cannot be made in laboratories; we have tried but it just can't be done 
D)  when a particle of matter and the corresponding particle of antimatter meet, they become pure energy 
E)  our telescopes clearly see many nearby antimatter stars in the Milky Way galaxy

Question 2

What happens to the positron created during the p-p chain of nuclear reactions inside the Sun?

Accepted Answer

A)  it merges with a proton to become a deuterium (heavy hydrogen) nucleus 
B)  it quickly collides with an electron and turns into gamma-ray energy 
C)  it ultimately forms an anti-helium nucleus 
D)  it turns quickly into a neutrino, which can escape from the Sun 
E)  it just sits there at the core of the Sun for billions of years, unable to interact
Section 16.3: The Solar Interior: Theory 
A)  it merges with a proton to become a deuterium (heavy hydrogen) nucleus 
B)  it quickly collides with an electron and turns into gamma-ray energy 
C)  it ultimately forms an anti-helium nucleus 
D)  it turns quickly into a neutrino, which can escape from the Sun 
E)  it just sits there at the core of the Sun for billions of years, unable to interact
Section 16.3: The Solar Interior: Theory

Question 3

The Global Oscillations Network Group (GONG) Project is engaged in:

Accepted Answer

A)  measuring where earthquakes happen around the Earth by the waves they generate 
B)  measuring the number of sunspots on the surface of the Sun at any given hour 
C)  measuring the quality of the "seeing" (the "jiggling" of the Earth's atmosphere) at all the major observatories around the world 
D)  measuring the pulsations of the Sun from stations around the world 
E)  measuring how problems on the World Wide Web are affecting the communication among astronomers 
A)  measuring where earthquakes happen around the Earth by the waves they generate 
B)  measuring the number of sunspots on the surface of the Sun at any given hour 
C)  measuring the quality of the "seeing" (the "jiggling" of the Earth's atmosphere) at all the major observatories around the world 
D)  measuring the pulsations of the Sun from stations around the world 
E)  measuring how problems on the World Wide Web are affecting the communication among astronomers

Question 4

Astronomers and physicists now believe they know what is happening to the missing neutrinos from the Sun (the neutrinos that our theories say should be emerging from the Sun, but our experiments in that underground mine could not find). These neutrinos are:

Accepted Answer

A)  not being produced by the Sun because our star's nuclear fusion period has ended 
B)  turning into a different type of neutrino in a neutrino oscillation 
C)  being converted to antimatter in the core of the Sun and being destroyed as they hit matter 
D)  changing course before they reach the Earth as they hit other neutrinos in space 
E)  all aimed at Bayonne, New Jersey, and our neutrino experiments are located elsewhere 
A)  not being produced by the Sun because our star's nuclear fusion period has ended 
B)  turning into a different type of neutrino in a neutrino oscillation 
C)  being converted to antimatter in the core of the Sun and being destroyed as they hit matter 
D)  changing course before they reach the Earth as they hit other neutrinos in space 
E)  all aimed at Bayonne, New Jersey, and our neutrino experiments are located elsewhere

Question 5

In an earlier era, some scientists suggested that the energy of the Sun comes from meteorites (or, more properly, meteoroids) falling into it and converting their falling motion into heat. Which of the following is part of the argument that shows this mechanism will not work?

Accepted Answer

A)  the antimatter in the Sun would make the meteorites explode before they could do this 
B)  a mass of meteorites equal to the mass of the Earth would have to fall in every century 
C)  the meteorites would eventually increase the mass of the Sun and change the orbits of the planets 
D)  since the Sun is made of gas, it does not have enough gravity to pull in meteorites 
E)  more than one of the above 
A)  the antimatter in the Sun would make the meteorites explode before they could do this 
B)  a mass of meteorites equal to the mass of the Earth would have to fall in every century 
C)  the meteorites would eventually increase the mass of the Sun and change the orbits of the planets 
D)  since the Sun is made of gas, it does not have enough gravity to pull in meteorites 
E)  more than one of the above

Question 6

Which of the following, produced at the core of the Sun, will take the shortest time to emerge from the Sun's photosphere (surface)?

Accepted Answer

A)  a photon (wave) of gamma-rays 
B)  a positron 
C)  a neutrino 
D)  a deuteron 
E)  an x-ray produced after radiation has interacted with matter in the core 
A)  a photon (wave) of gamma-rays 
B)  a positron 
C)  a neutrino 
D)  a deuteron 
E)  an x-ray produced after radiation has interacted with matter in the core

Question 7

The Sun is an enormous ball of gas. Left to itself, a ball of so many atoms should collapse under its own tremendous gravity. Why is our Sun not collapsing?

Accepted Answer

A)  the gravity of the planets around the Sun pulls its material outward, preventing collapse 
B)  the pressure of the corona keeps the Sun's main body of gases confined to a small volume 
C)  nuclear fusion in the core keeps the temperature and the pressure inside the Sun at a high enough level so that gravity is balanced 
D)  neutrinos from the core exert an enormous pressure on the layers of the Sun as they travel outward; this pressure is more than enough to keep our star from collapsing 
E)  you can't fool me, the Sun is shrinking all the time, it just happens very slowly 
A)  the gravity of the planets around the Sun pulls its material outward, preventing collapse 
B)  the pressure of the corona keeps the Sun's main body of gases confined to a small volume 
C)  nuclear fusion in the core keeps the temperature and the pressure inside the Sun at a high enough level so that gravity is balanced 
D)  neutrinos from the core exert an enormous pressure on the layers of the Sun as they travel outward; this pressure is more than enough to keep our star from collapsing 
E)  you can't fool me, the Sun is shrinking all the time, it just happens very slowly

Question 8

A college friend of yours who has been postponing taking any science courses hears you talking about the generation of nuclear energy in the Sun and makes the following observation: "The whole idea of the atomic nucleus is pretty ridiculous. If an oxygen nucleus consists of eight protons and eight neutrons, the charge on that nucleus is positive. Since even I learned in high school that like charges repel, such a nucleus would find all its positive protons repelling and quickly fall apart." How would you answer his argument?

Accepted Answer

A)  gravity is much stronger than electric repulsion and holds every nucleus together 
B)  the neutrons in the nucleus are negative, so they cancel the positive charge on the protons 
C)  the nuclear force, which is attractive over short distances like the nucleus, and stronger than electricity, holds the nucleus together 
D)  the electrons outside the nucleus repel the protons and keep them inside the nucleus 
E)  there is no answer; scientists do not have a clue about how the nucleus manages to keep itself together 
A)  gravity is much stronger than electric repulsion and holds every nucleus together 
B)  the neutrons in the nucleus are negative, so they cancel the positive charge on the protons 
C)  the nuclear force, which is attractive over short distances like the nucleus, and stronger than electricity, holds the nucleus together 
D)  the electrons outside the nucleus repel the protons and keep them inside the nucleus 
E)  there is no answer; scientists do not have a clue about how the nucleus manages to keep itself together

Question 9

The antimatter version of an electron is called a

Accepted Answer

A)  proton 
B)  neutrino 
C)  antitron 
D)  positron 
E)  gammatron 
A)  proton 
B)  neutrino 
C)  antitron 
D)  positron 
E)  gammatron

Question 10

Which of the following is NOT one of the fundamental particles that we find inside atoms?

Accepted Answer

A)  protons 
B)  neutrons 
C)  positrons 
D)  electrons 
E)  all four of the above are found in most atoms 
A)  protons 
B)  neutrons 
C)  positrons 
D)  electrons 
E)  all four of the above are found in most atoms

Question 11

Which of the following best describes the first set of experiments, using chlorine traps, that were searching for electron neutrinos from the Sun?

Accepted Answer

A)  All the experiments had technical problems detecting neutrinos, which are very "antisocial" and thus very hard to catch 
B)  The experiments worked OK, but they found no neutrinos at all; not a single one 
C)  All the neutrinos found in these experiments were one of the other two types of neutrinos, not the electron neutrino that we expect coming from nuclear fusion in the Sun 
D)  Now that they are working right, the chlorine experiments have found all the neutrinos that our models of the Sun have predicted should be coming 
E)  The chlorine experiments found only between 1/3 the number of electron neutrinos arriving from the Sun that our models predicted should be coming 
A)  All the experiments had technical problems detecting neutrinos, which are very "antisocial" and thus very hard to catch 
B)  The experiments worked OK, but they found no neutrinos at all; not a single one 
C)  All the neutrinos found in these experiments were one of the other two types of neutrinos, not the electron neutrino that we expect coming from nuclear fusion in the Sun 
D)  Now that they are working right, the chlorine experiments have found all the neutrinos that our models of the Sun have predicted should be coming 
E)  The chlorine experiments found only between 1/3 the number of electron neutrinos arriving from the Sun that our models predicted should be coming

Question 12

If the "fuel" for nuclear fusion is nuclei of hydrogen, and the Earth's oceans are filled with hydrogen atoms in water all being jostled together, why isn't there a lot of fusion happening in our oceans?

Accepted Answer

A)  the hydrogen in our oceans is the wrong type of hydrogen for fusion 
B)  for hydrogen nuclei to fuse, they must get very close to each other, which the nuclei in the oceans cannot do 
C)  for hydrogen to fuse, the nuclei must first join together in long chains of atoms 
D)  on Earth, only hydrogen that is in deep mines under the Earth is far enough underground for fusion 
E)  you can't fool me, hydrogen in the Earth's oceans does undergo fusion; that's what keeps our oceans warm 
A)  the hydrogen in our oceans is the wrong type of hydrogen for fusion 
B)  for hydrogen nuclei to fuse, they must get very close to each other, which the nuclei in the oceans cannot do 
C)  for hydrogen to fuse, the nuclei must first join together in long chains of atoms 
D)  on Earth, only hydrogen that is in deep mines under the Earth is far enough underground for fusion 
E)  you can't fool me, hydrogen in the Earth's oceans does undergo fusion; that's what keeps our oceans warm

Question 13

Which part of the Sun has the greatest density?

Accepted Answer

A)  the photosphere 
B)  the core 
C)  the convection region 
D)  the corona 
E)  you can't fool me; all the Sun's parts have the same density
Section 16.4: The Solar Interior: Observations 
A)  the photosphere 
B)  the core 
C)  the convection region 
D)  the corona 
E)  you can't fool me; all the Sun's parts have the same density
Section 16.4: The Solar Interior: Observations

Question 14

Which of the following is NOT an experiment that is searching for neutrinos coming from the Sun?

Accepted Answer

A)  looking for radioactive argon atoms in a tank of cleaning fluid deep in an underground mine 
B)  looking for changes in the Doppler shift of lines in the atmosphere of the Sun 
C)  looking for radioactive gallium in a vast quantity of ordinary gallium 
D)  looking with sensitive light meters in a giant vat of pure water deep underground in Japan 
E)  all of the above are ways to search for neutrinos 
A)  looking for radioactive argon atoms in a tank of cleaning fluid deep in an underground mine 
B)  looking for changes in the Doppler shift of lines in the atmosphere of the Sun 
C)  looking for radioactive gallium in a vast quantity of ordinary gallium 
D)  looking with sensitive light meters in a giant vat of pure water deep underground in Japan 
E)  all of the above are ways to search for neutrinos

Question 15

When energy is first produced by fusion deep in the core of the star, that energy moves outward mostly by what process?

Accepted Answer

A)  convection 
B)  radiation 
C)  conduction 
D)  theoretical modeling 
E)  none of the above 
A)  convection 
B)  radiation 
C)  conduction 
D)  theoretical modeling 
E)  none of the above

Question 16

Where in the Sun does fusion of hydrogen occur?

Accepted Answer

A)  only in the core 
B)  only near the photosphere (its visible surface layer) 
C)  pretty much throughout the entire body of the Sun 
D)  only in the layer where there is a lot of convection going on 
E)  nowhere 
A)  only in the core 
B)  only near the photosphere (its visible surface layer) 
C)  pretty much throughout the entire body of the Sun 
D)  only in the layer where there is a lot of convection going on 
E)  nowhere

Exam 16: The Sun: a Nuclear Powerhouse

Which of the following statements about antimatter is true ?

What happens to the positron created during the p-p chain of nuclear reactions inside the Sun?

The Global Oscillations Network Group (GONG) Project is engaged in:

Astronomers and physicists now believe they know what is happening to the missing neutrinos from the Sun (the neutrinos that our theories say should be emerging from the Sun, but our experiments in that underground mine could not find). These neutrinos are:

In an earlier era, some scientists suggested that the energy of the Sun comes from meteorites (or, more properly, meteoroids) falling into it and converting their falling motion into heat. Which of the following is part of the argument that shows this mechanism will not work?

Which of the following, produced at the core of the Sun, will take the shortest time to emerge from the Sun's photosphere (surface)?

The Sun is an enormous ball of gas. Left to itself, a ball of so many atoms should collapse under its own tremendous gravity. Why is our Sun not collapsing?

The antimatter version of an electron is called a

Which of the following is NOT one of the fundamental particles that we find inside atoms?

Which of the following best describes the first set of experiments, using chlorine traps, that were searching for electron neutrinos from the Sun?

If the "fuel" for nuclear fusion is nuclei of hydrogen, and the Earth's oceans are filled with hydrogen atoms in water all being jostled together, why isn't there a lot of fusion happening in our oceans?

Which part of the Sun has the greatest density?

Which of the following is NOT an experiment that is searching for neutrinos coming from the Sun?

When energy is first produced by fusion deep in the core of the star, that energy moves outward mostly by what process?

Where in the Sun does fusion of hydrogen occur?

Science and the Universe: a Brief Tour

Observing the Sky: the Birth of Astronomy

Orbits and Gravity

Earth, Moon, and Sky

Radiation and Spectra

Astronomical Instruments

Other Worlds: an Introduction to the Solar System

Earth As a Planet

Cratered Worlds: the Moon and Mercury

Earthlike Planets: Venus and Mars

The Giant Planets

Rings, Moons, and Pluto

Comets and Asteroids: Debris of the Solar System

Cosmic Samples and the Origin of the Solar System

The Sun: a Garden-Variety Star

Analyzing Starlight

The Stars: a Celestial Census

Celestial Distances

Between the Stars

The Birth of Stars and the Discovery of Planets Outside the Solar System

Stars From Adolescence to Old Age

The Death of Stars

Black Holes and Curved Space-Time

The Milky Way Galaxy

Galaxies

Active Galaxies, Quasars, and Supermassive Black Holes

The Evolution and Distribution of Galaxies

The Big Bang

Life in the Universe

Filters