Question 1

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 2

Particles that decay via the strong interaction have lifetimes of the order of

Accepted Answer

A) 10-10 s 
B) 10-15 s 
C) 10-20 s 
D) 10-23 s 
E) 10-27 s 
A) 10-10 s 
B) 10-15 s 
C) 10-20 s 
D) 10-23 s 
E) 10-27 s

Question 3

The field quanta that mediate the weak nuclear force are

Accepted Answer

A) photons 
B) gravitons 
C) GUTs 
D) gluons 
E) weak vector bosons 
A) photons 
B) gravitons 
C) GUTs 
D) gluons 
E) weak vector bosons

Question 4

The charge of the s quark is

Accepted Answer

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

Question 5

The numbers L = +1 and B = -1 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 6

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 7

Particles that participate in the strong nuclear 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

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

Molecular forces and most of the everyday forces we observe among macroscopic objects are best understood in terms of

Accepted Answer

A) the strong nuclear (hadronic)interaction. 
B) the electromagnetic interaction. 
C) the weak nuclear interaction. 
D) the gravitational interaction. 
E) None of these is correct. 
A) the strong nuclear (hadronic)interaction. 
B) the electromagnetic interaction. 
C) the weak nuclear interaction. 
D) the gravitational interaction. 
E) None of these is correct.

Question 10

The field quanta associated with the hadronic force between quarks are called

Accepted Answer

A) photons 
B) gravitons 
C) GUTs 
D) gluons 
E) vector bosons 
A) photons 
B) gravitons 
C) GUTs 
D) gluons 
E) vector bosons

Question 11

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 12

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 13

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 14

The Coulomb force in the classical sense is understood in terms of electric fields.However,in quantum mechanics,the Coulomb force is described in terms of exchange of virtual photons between the charged particles.Why doesn't the creation of the virtual photons violate the principle of conservation of energy?

Accepted Answer

A) This is because in quantum mechanics energy is not conserved. 
B) The uncertainty principle,   allows photons to be created provided they are absorbed within the time interval $\Delta$t. 
C) The photons do not have any energy since they are massless. 
D) The virtual photons are not real photons and hence do not carry any energy. 
E) None of these is correct. 
A) This is because in quantum mechanics energy is not conserved. 
B) The uncertainty principle,   allows photons to be created provided they are absorbed within the time interval $\Delta$t. 
C) The photons do not have any energy since they are massless. 
D) The virtual photons are not real photons and hence do not carry any energy. 
E) None of these is correct.

Question 15

We think that the universe is expanding because

Accepted Answer

A) the light from distant galaxies is very faint. 
B) the light from distant galaxies is very bright. 
C) distant galaxies are very small. 
D) the light from distant galaxies is blueshifted. 
E) the light from distant galaxies is redshifted. 
A) the light from distant galaxies is very faint. 
B) the light from distant galaxies is very bright. 
C) distant galaxies are very small. 
D) the light from distant galaxies is blueshifted. 
E) the light from distant galaxies is redshifted.

Question 16

The reaction $\mu$- $\to$ e- + $ \bar{v}_{\mathrm{e}} $  + $ \bar{v}_{\mu}$ conserves

Accepted Answer

A) muon lepton number but not electron lepton number. 
B) electron lepton number but not muon lepton number. 
C) neither muon lepton nor electron lepton number. 
D) both muon and electron lepton numbers. 
E) None of these is correct. 
A) muon lepton number but not electron lepton number. 
B) electron lepton number but not muon lepton number. 
C) neither muon lepton nor electron lepton number. 
D) both muon and electron lepton numbers. 
E) None of these is correct.

Question 17

Redshift measurements of a galaxy yield a recession of 1000 km/s.Hubble's constant H is 23 km/s/106 c·y.The distance to the galaxy is approximately

Accepted Answer

A) 23 $\times$ 106 c·y 
B) 37 $\times$ 106 c·y 
C) 44 $\times$ 106 c·y 
D) 52 $\times$ 106 c·y 
E) 61 $\times$ 106 c·y 
A) 23 $\times$ 106 c·y 
B) 37 $\times$ 106 c·y 
C) 44 $\times$ 106 c·y 
D) 52 $\times$ 106 c·y 
E) 61 $\times$ 106 c·y

Question 18

Virtual photons are particles that mediate the Coulomb force and travel at the speed of light.What is the approximate energy of the virtual photons that mediate between the electron in the ground state and proton in a hydrogen atom? The radius of the electron in the ground state is 0.053 nm.

Accepted Answer

A) 100 eV 
B) 500 eV 
C) 1000 eV 
D) 4 keV 
E) 0.5 MeV 
A) 100 eV 
B) 500 eV 
C) 1000 eV 
D) 4 keV 
E) 0.5 MeV

Question 19

The property of the universe that primarily determines whether the universe will expand forever or eventually stop its expansion and contract is

Accepted Answer

A) its average abundance of heavy elements. 
B) how much of its gas has been converted into stars. 
C) its average temperature. 
D) its total mass. 
E) dependent on the amount of helium in the universe. 
A) its average abundance of heavy elements. 
B) how much of its gas has been converted into stars. 
C) its average temperature. 
D) its total mass. 
E) dependent on the amount of helium in the universe.

Question 20

Mesons are particles that mediate the strong nuclear force.They are thought to travel at near the speed of light and exist over a distance between two nucleons in the nucleus $\backsim$1.5 fm.The mass of the mesons is of the order

Accepted Answer

A) 10 MeV/c2. 
B) 150 MeV/c2. 
C) 550 MeV/c2. 
D) 1000 MeV/c2. 
E) 3000 MeV/c2. 
A) 10 MeV/c2. 
B) 150 MeV/c2. 
C) 550 MeV/c2. 
D) 1000 MeV/c2. 
E) 3000 MeV/c2.

Exam 41: Elementary Particles and the Beginning of the Universe

Current thought is that all matter is composed of

Particles that decay via the strong interaction have lifetimes of the order of

The field quanta that mediate the weak nuclear force are

The charge of the s quark is

The numbers L = +1 and B = -1 describe

The cosmic background radiation strongly suggests that

Particles that participate in the strong nuclear interaction are called

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

Molecular forces and most of the everyday forces we observe among macroscopic objects are best understood in terms of

The field quanta associated with the hadronic force between quarks are called

In the standard model,weak charge is

Spin particles

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

We think that the universe is expanding because

The reaction μ\muμ - →\to→ e- + vˉe \bar{v}_{\mathrm{e}} vˉe​ + vˉμ \bar{v}_{\mu}vˉμ​ conserves

Redshift measurements of a galaxy yield a recession of 1000 km/s.Hubble's constant H is 23 km/s/106 c·y.The distance to the galaxy is approximately

Virtual photons are particles that mediate the Coulomb force and travel at the speed of light.What is the approximate energy of the virtual photons that mediate between the electron in the ground state and proton in a hydrogen atom? The radius of the electron in the ground state is 0.053 nm.

The property of the universe that primarily determines whether the universe will expand forever or eventually stop its expansion and contract is

Mesons are particles that mediate the strong nuclear force.They are thought to travel at near the speed of light and exist over a distance between two nucleons in the nucleus ∽\backsim∽ 1.5 fm.The mass of the mesons is of the order

Systems of Measurement

Motion in One Dimension

Motion in Two and Three Dimensions

Newtons Laws

Applications of Newtons Laws

Work and Energy

Conservation of Energy

Systems of Particles and Conservation of Linear Momentum

Rotation

Conservation of Angular Momentum

Gravity

Static Equilibrium and Elasticity

Fluids

Oscillations

Wave Motion

Superposition and Standing Waves

Temperature and the Kinetic Theory of Gases

Heat and the First Law of Thermodynamics

The Second Law of Thermodynamics

Thermal Properties and Processes

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 $\mu$ ^- $\to$ e^- + $\bar{v}_{\mathrm{e}}$ + $\bar{v}_{\mu}$ conserves

Redshift measurements of a galaxy yield a recession of 1000 km/s.Hubble's constant H is 23 km/s/10⁶ c·y.The distance to the galaxy is approximately

Mesons are particles that mediate the strong nuclear force.They are thought to travel at near the speed of light and exist over a distance between two nucleons in the nucleus $\backsim$ 1.5 fm.The mass of the mesons is of the order