Question 1

The numbers L = 0 and B = 0 describe

Accepted Answer

A)  a particle other than a lepton or a baryon. 
B)  a lepton and an antibaryon. 
C)  an antilepton and a baryon. 
D)  an antilepton and an antibaryon. 
E)  a lepton and a baryon. 
A)  a particle other than a lepton or a baryon. 
B)  a lepton and an antibaryon. 
C)  an antilepton and a baryon. 
D)  an antilepton and an antibaryon. 
E)  a lepton and a baryon.

Question 2

The fact that the reaction 37Cl +   $\rightarrow$37Ar + e- is not observed whereas the reaction
P +  $\rightarrow$ n + e+ is observed is understandable in terms of the conservation of

Accepted Answer

A)  baryon number 
B)  energy 
C)  lepton number 
D)  charge 
E)  angular momentum 
A)  baryon number 
B)  energy 
C)  lepton number 
D)  charge 
E)  angular momentum

Question 3

In quantum electrodynamics (QED), the electromagnetic field is described in terms of

Accepted Answer

A)  the interaction of electrons. 
B)  hadrons. 
C)  action at a distance. 
D)  the weak nuclear interaction. 
E)  the interaction of photons. 
A)  the interaction of electrons. 
B)  hadrons. 
C)  action at a distance. 
D)  the weak nuclear interaction. 
E)  the interaction of photons.

Question 4

Which of the following are possible combinations of quarks?

Accepted Answer

A)  1,2,3,5,6 
B)  1,3,5,6 
C)  2,3,5,6 
D)  1,3,4,5 
E)  1,3,4,5,6 
A)  1,2,3,5,6 
B)  1,3,5,6 
C)  2,3,5,6 
D)  1,3,4,5 
E)  1,3,4,5,6

Question 5

In the standard model, weak charge is

Accepted Answer

A)  the charge associated with the gravitational force. 
B)  carried by leptons and quarks. 
C)  carried by quarks and gluons but not leptons. 
D)  carried by photons. 
E)  a property of the W± and the Z particles. 
A)  the charge associated with the gravitational force. 
B)  carried by leptons and quarks. 
C)  carried by quarks and gluons but not leptons. 
D)  carried by photons. 
E)  a property of the W± and the Z particles.

Question 6

The reaction e+ + e- $\rightarrow$$\gamma$ + $\gamma$

Accepted Answer

A)  describes the annihilation of a positron. 
B)  has a large probability of occurrence only if the positron is at rest or nearly at rest. 
C)  requires two photons moving in opposite directions to conserve linear momentum. 
D)  is an electron-positron reaction. 
E)  All of these are correct. 
A)  describes the annihilation of a positron. 
B)  has a large probability of occurrence only if the positron is at rest or nearly at rest. 
C)  requires two photons moving in opposite directions to conserve linear momentum. 
D)  is an electron-positron reaction. 
E)  All of these are correct.

Question 7

According to Hubble's law, the age of the universe is

Accepted Answer

A)  approximately 6000 years. 
B)  less than 6000 years. 
C)  roughly 1 billion years. 
D)  too great to estimate. 
E)  between 10 and 15 billion years. 
A)  approximately 6000 years. 
B)  less than 6000 years. 
C)  roughly 1 billion years. 
D)  too great to estimate. 
E)  between 10 and 15 billion years.

Question 8

Conservation laws that describe events involving the elementary particles include the conservation of

Accepted Answer

A)  energy. 
B)  linear and angular momentum. 
C)  electric charge. 
D)  baryon and lepton numbers. 
E)  All of these are correct. 
A)  energy. 
B)  linear and angular momentum. 
C)  electric charge. 
D)  baryon and lepton numbers. 
E)  All of these are correct.

Question 9

A thousand years after the "Big Bang" the background temperature of the universe was at  $\backsim$ 105 K. The peak wavelength of the blackbody radiation at that temperature is

Accepted Answer

A)  29 nm 
B)  290 nm 
C)  56 nm 
D)  560 nm 
E)  730 nm 
A)  29 nm 
B)  290 nm 
C)  56 nm 
D)  560 nm 
E)  730 nm

Question 10

The cosmic background radiation strongly suggests that

Accepted Answer

A)  the energy radiated from the quasars is redshifted. 
B)  the universe has always been as it is today. 
C)  the universe evolved from a cold, rarified state. 
D)  the universe evolved from a hot, uniform state. 
E)  matter is continuously being created. 
A)  the energy radiated from the quasars is redshifted. 
B)  the universe has always been as it is today. 
C)  the universe evolved from a cold, rarified state. 
D)  the universe evolved from a hot, uniform state. 
E)  matter is continuously being created.

Question 11

Hadrons are thought to be

Accepted Answer

A)  without structure. 
B)  composed of quarks. 
C)  composed of electrons. 
D)  responsible for the gravitational interaction. 
E)  extremely stable particles. 
A)  without structure. 
B)  composed of quarks. 
C)  composed of electrons. 
D)  responsible for the gravitational interaction. 
E)  extremely stable particles.

Question 12

There is evidence that the universe is expanding like a loaf of raisin bread baking in an oven. This means that

Accepted Answer

A)  some clusters of galaxies are not getting farther away from other clusters of galaxies. 
B)  the expansion looks different from each cluster of galaxies. 
C)  the expansion looks the same from each cluster of galaxies. 
D)  we should be able to determine the location of the center of the expansion. 
E)  the universe will eventually collapse. 
A)  some clusters of galaxies are not getting farther away from other clusters of galaxies. 
B)  the expansion looks different from each cluster of galaxies. 
C)  the expansion looks the same from each cluster of galaxies. 
D)  we should be able to determine the location of the center of the expansion. 
E)  the universe will eventually collapse.

Question 13

In the Standard Model, as with the leptons, there are 3 generations of quarks (u&d, c&s, and t&b). The reason for this is

Accepted Answer

A)  because a baryon contains 3 quarks. 
B)  because the electric charge of the quarks is +1/3 or -2/3 of e. 
C)  because each quark has a baryon number of 1/3. 
D)  all of the above. 
E)  something we do not yet understand. 
A)  because a baryon contains 3 quarks. 
B)  because the electric charge of the quarks is +1/3 or -2/3 of e. 
C)  because each quark has a baryon number of 1/3. 
D)  all of the above. 
E)  something we do not yet understand.

Question 14

Leptons

Accepted Answer

A)  are less massive than the lightest hadron. 
B)  include electrons, muons, and neutrinos. 
C)  participate in the weak interaction. 
D)  have significantly different masses. 
E)  All of these are correct. 
A)  are less massive than the lightest hadron. 
B)  include electrons, muons, and neutrinos. 
C)  participate in the weak interaction. 
D)  have significantly different masses. 
E)  All of these are correct.

Question 15

The charge of the particle   is

Accepted Answer

A)  e 
B)  (1/3)e 
C)  (-2/3)e 
D)  -e 
E)  2e 
A)  e 
B)  (1/3)e 
C)  (-2/3)e 
D)  -e 
E)  2e

Question 16

Redshift measurements of a galaxy yield a recession of 1700 km/s. Hubble's constant H is 23 km/s/106 c·y. The distance to the galaxy is approximately

Accepted Answer

A)  36 * 106 c·y 
B)  47 * 106 c·y 
C)  53 *106 c·y 
D)  66 * 106 c·y 
E)  74 * 106 c·y 
A)  36 * 106 c·y 
B)  47 * 106 c·y 
C)  53 *106 c·y 
D)  66 * 106 c·y 
E)  74 * 106 c·y

Question 17

Spin   particles

Accepted Answer

A)  have spins that are integral multiples of   
B)  are called fermions. 
C)  obey the Pauli exclusion principle. 
D)  include protons, neutrons, and neutrinos. 
E)  All of these are correct. 
A)  have spins that are integral multiples of   
B)  are called fermions. 
C)  obey the Pauli exclusion principle. 
D)  include protons, neutrons, and neutrinos. 
E)  All of these are correct.

Question 18

Current thought is that all matter is composed of

Accepted Answer

A)  six quarks. 
B)  four quarks and four leptons. 
C)  six leptons. 
D)  six quarks and four leptons. 
E)  six quarks and six leptons. 
A)  six quarks. 
B)  four quarks and four leptons. 
C)  six leptons. 
D)  six quarks and four leptons. 
E)  six quarks and six leptons.

Question 19

Particles that have zero spin or integral spin

Accepted Answer

A)  are called bosons. 
B)  are called fermions. 
C)  must be in different quantum states. 
D)  include protons, neutrons, and neutrinos. 
E)  None of these is correct. 
A)  are called bosons. 
B)  are called fermions. 
C)  must be in different quantum states. 
D)  include protons, neutrons, and neutrinos. 
E)  None of these is correct.

Question 20

Particles that participate in the weak interaction but not the strong interaction are called

Accepted Answer

A)  neutrinos 
B)  hadrons 
C)  leptons 
D)  electrons 
E)  photons 
A)  neutrinos 
B)  hadrons 
C)  leptons 
D)  electrons 
E)  photons

The numbers L = 0 and B = 0 describe

In quantum electrodynamics (QED), the electromagnetic field is described in terms of

Which of the following are possible combinations of quarks?

In the standard model, weak charge is

The reaction e⁺ + e^- $\rightarrow$ $\gamma$ + $\gamma$

According to Hubble's law, the age of the universe is

Conservation laws that describe events involving the elementary particles include the conservation of

A thousand years after the "Big Bang" the background temperature of the universe was at $\backsim$ 10⁵ K. The peak wavelength of the blackbody radiation at that temperature is

The cosmic background radiation strongly suggests that

Hadrons are thought to be

There is evidence that the universe is expanding like a loaf of raisin bread baking in an oven. This means that

In the Standard Model, as with the leptons, there are 3 generations of quarks (u&d, c&s, and t&b). The reason for this is

Leptons

The charge of the particle is

Redshift measurements of a galaxy yield a recession of 1700 km/s. Hubble's constant H is 23 km/s/10⁶ c·y. The distance to the galaxy is approximately

Spin particles

Current thought is that all matter is composed of

Particles that have zero spin or integral spin

Particles that participate in the weak interaction but not the strong interaction are called

The Electric Field I: Discrete Charge Distributions

The Electric Field II: Continuous Charge Distributions

Electric Potential

Capacitance

Electric Current and Direct-Current Circuits

The Magnetic Field

Sources of the Magnetic Field

Magnetic Induction

Alternating-Current Circuits

Maxwells Equations and Electromagnetic Waves

Properties of Light

Optical Images

Interference and Diffraction

Wave Particle Duality and Quantum Physics

Applications of the Schrodinger Equation

Atoms

Molecules

Solids and the Theory of Conduction

Relativity

Nuclear Physics

Filters

Exam 21: Elementary Particles and the Beginning of the Universe

The numbers L = 0 and B = 0 describe

The fact that the reaction 37Cl + →\rightarrow→ 37Ar + e- is not observed whereas the reaction P +11efbfba_b1a8_16af_a19f_e32c5f3598e7_TB6081_00 →\rightarrow→ n + e+ is observed is understandable in terms of the conservation of

In quantum electrodynamics (QED), the electromagnetic field is described in terms of

Which of the following are possible combinations of quarks?

In the standard model, weak charge is

The reaction e+ + e- →\rightarrow→γ\gammaγ + γ\gammaγ

According to Hubble's law, the age of the universe is

Conservation laws that describe events involving the elementary particles include the conservation of

A thousand years after the "Big Bang" the background temperature of the universe was at ∽\backsim∽ 105 K. The peak wavelength of the blackbody radiation at that temperature is

The cosmic background radiation strongly suggests that

Hadrons are thought to be

There is evidence that the universe is expanding like a loaf of raisin bread baking in an oven. This means that

In the Standard Model, as with the leptons, there are 3 generations of quarks (u&d, c&s, and t&b). The reason for this is

Leptons

The charge of the particle is

Redshift measurements of a galaxy yield a recession of 1700 km/s. Hubble's constant H is 23 km/s/106 c·y. The distance to the galaxy is approximately

Spin particles

Current thought is that all matter is composed of

Particles that have zero spin or integral spin

Particles that participate in the weak interaction but not the strong interaction are called

The Electric Field I: Discrete Charge Distributions

The Electric Field II: Continuous Charge Distributions

Electric Potential

Capacitance

Electric Current and Direct-Current Circuits

The Magnetic Field

Sources of the Magnetic Field

Magnetic Induction

Alternating-Current Circuits

Maxwells Equations and Electromagnetic Waves

Properties of Light

Optical Images

Interference and Diffraction

Wave Particle Duality and Quantum Physics

Applications of the Schrodinger Equation

Atoms

Molecules

Solids and the Theory of Conduction

Relativity

Nuclear Physics

Filters

The reaction e⁺ + e^- $\rightarrow$ $\gamma$ + $\gamma$

A thousand years after the "Big Bang" the background temperature of the universe was at $\backsim$ 10⁵ K. The peak wavelength of the blackbody radiation at that temperature is

Redshift measurements of a galaxy yield a recession of 1700 km/s. Hubble's constant H is 23 km/s/10⁶ c·y. The distance to the galaxy is approximately