Question 1

In laser fusion, the laser light is:

Accepted Answer

A) emitted by the reacting nuclei 
B) used to cause transitions between nuclear energy levels 
C) used to cause transitions between atomic energy levels 
D) used to replace the emitted gamma rays 
E) used to heat the fuel pellet 
A) emitted by the reacting nuclei 
B) used to cause transitions between nuclear energy levels 
C) used to cause transitions between atomic energy levels 
D) used to replace the emitted gamma rays 
E) used to heat the fuel pellet

Question 2

To produce energy by fusion of two nuclei, the nuclei must:

Accepted Answer

A) have at least several thousand electron volts of kinetic energy 
B) both be above iron in mass number 
C) have more neutrons than protons 
D) be unstable 
E) be magic number nuclei 
A) have at least several thousand electron volts of kinetic energy 
B) both be above iron in mass number 
C) have more neutrons than protons 
D) be unstable 
E) be magic number nuclei

Question 3

Which one of the following represents a fission reaction that can be activated by slow neutrons?

Accepted Answer

A) "238U92 + 1n0 $\rightarrow$90Kr36 + 146Cs55 + 2H1 + 1n0" 
B) "239Pu94 + 1n0 $\rightarrow$ 96Sr38 + 141Ba56 + 31n0" 
C) "238U92 $\rightarrow$234Th90 + 4He2" 
D) "3H1 + 2H1 $\rightarrow$4He2 + 1n0" 
E) "107Ag47 + 1n0 $\rightarrow$ 108Ag47 $\rightarrow$ 108Cd48 + 0e-1" 
A) "238U92 + 1n0 $\rightarrow$90Kr36 + 146Cs55 + 2H1 + 1n0" 
B) "239Pu94 + 1n0 $\rightarrow$ 96Sr38 + 141Ba56 + 31n0" 
C) "238U92 $\rightarrow$234Th90 + 4He2" 
D) "3H1 + 2H1 $\rightarrow$4He2 + 1n0" 
E) "107Ag47 + 1n0 $\rightarrow$ 108Ag47 $\rightarrow$ 108Cd48 + 0e-1"

Question 4

When 236U fissions the fragments are:

Accepted Answer

A) always 140Xe and 94Sr 
B) always identical 
C) never 140Xe and 94Sr 
D) never identical 
E) none of the above 
A) always 140Xe and 94Sr 
B) always identical 
C) never 140Xe and 94Sr 
D) never identical 
E) none of the above

Question 5

The barrier to fission comes about because the fragments:

Accepted Answer

A) attract each other via the strong nuclear force 
B) repel each other electrically 
C) produce magnetic fields 
D) have large masses 
E) attract electrons electrically 
A) attract each other via the strong nuclear force 
B) repel each other electrically 
C) produce magnetic fields 
D) have large masses 
E) attract electrons electrically

Question 6

Nuclear fusion in stars produces all the chemical elements with mass numbers less than:

Accepted Answer

A) 56 
B) 66 
C) 70 
D) 82 
E) 92 
A) 56 
B) 66 
C) 70 
D) 82 
E) 92

Question 7

The binding energy per nucleon:

Accepted Answer

A) increases for all fission events 
B) increases for some, but not all, fusion events 
C) decreases for all fusion events 
D) decreases for some, but not all, fission events 
E) remains the same for all fusion events 
A) increases for all fission events 
B) increases for some, but not all, fusion events 
C) decreases for all fusion events 
D) decreases for some, but not all, fission events 
E) remains the same for all fusion events

Question 8

Separation of the isotopes of uranium requires a physical, rather than chemical, method because:

Accepted Answer

A) mixing other chemicals with uranium is too dangerous 
B) the isotopes are chemically the same 
C) the isotopes have exactly the same number of neutrons per nucleus 
D) natural uranium contains only 0.7% 235U 
E) uranium is the heaviest element in nature 
A) mixing other chemicals with uranium is too dangerous 
B) the isotopes are chemically the same 
C) the isotopes have exactly the same number of neutrons per nucleus 
D) natural uranium contains only 0.7% 235U 
E) uranium is the heaviest element in nature

Question 9

The energy released in a complete proton-proton cycle is about:

Accepted Answer

A) 3 keV 
B) 30 keV 
C) 3 MeV 
D) 30 MeV 
E) 300 MeV 
A) 3 keV 
B) 30 keV 
C) 3 MeV 
D) 30 MeV 
E) 300 MeV

Question 10

The barrier to fusion comes about because protons:

Accepted Answer

A) attract each other via the strong nuclear force 
B) repel each other electrically 
C) produce magnetic fields 
D) attract neutrons via the strong nuclear force 
E) attract electrons electrically 
A) attract each other via the strong nuclear force 
B) repel each other electrically 
C) produce magnetic fields 
D) attract neutrons via the strong nuclear force 
E) attract electrons electrically

Question 11

An explosion does not result from a small piece of 235U because:

Accepted Answer

A) "it does not fission" 
B) "the neutrons released move too fast" 
C) "238U is required" 
D) "too many neutrons escape, preventing a chain reaction from starting" 
E) "a few neutrons must be injected to start the chain reaction" 
A) "it does not fission" 
B) "the neutrons released move too fast" 
C) "238U is required" 
D) "too many neutrons escape, preventing a chain reaction from starting" 
E) "a few neutrons must be injected to start the chain reaction"

Question 12

Consider all possible fission events.Which of the following statements is true?

Accepted Answer

A) Light initial fragments have more protons than neutrons and heavy initial fragments have fewer protons than neutrons 
B) Heavy initial fragments have more protons than neutrons and light initial fragments have fewer protons than neutrons 
C) All initial fragments have more protons than neutrons 
D) All initial fragments have about the same number of protons and neutrons 
E) All initial fragments have more neutrons than protons 
A) Light initial fragments have more protons than neutrons and heavy initial fragments have fewer protons than neutrons 
B) Heavy initial fragments have more protons than neutrons and light initial fragments have fewer protons than neutrons 
C) All initial fragments have more protons than neutrons 
D) All initial fragments have about the same number of protons and neutrons 
E) All initial fragments have more neutrons than protons

Question 13

Most laser fusion projects attempt:

Accepted Answer

A) proton-proton fusion 
B) proton-deuteron fusion 
C) deuteron-deuteron fusion 
D) deuteron-triton fusion 
E) triton-triton fusion 
A) proton-proton fusion 
B) proton-deuteron fusion 
C) deuteron-deuteron fusion 
D) deuteron-triton fusion 
E) triton-triton fusion

Question 14

A nuclear reactor is operating at a certain power level, with its multiplication factor adjusted to unity.The control rods are now used to reduce the power output to one-half its former value.After the reduction in power the multiplication factor is maintained at:

Accepted Answer

A) 1/4 
B) 1/2 
C) 1 
D) 2 
E) 4 
A) 1/4 
B) 1/2 
C) 1 
D) 2 
E) 4

Question 15

Lawson's number is 1020 s.m-3.If the density of deuteron nuclei is 2 *1021 m-3 what should the confinement time be to achieve sustained fusion?

Accepted Answer

A) 16 ms 
B) 50 ms 
C) 160 ms 
D) 250 ms 
E) 20 s 
A) 16 ms 
B) 50 ms 
C) 160 ms 
D) 250 ms 
E) 20 s

Question 16

The energy supplied by a thermal neutron in a fission event is essentially its:

Accepted Answer

A) excitation energy 
B) binding energy 
C) kinetic energy 
D) rest energy 
E) electric potential energy 
A) excitation energy 
B) binding energy 
C) kinetic energy 
D) rest energy 
E) electric potential energy

Question 17

High temperatures are required in thermonuclear fusion so that:

Accepted Answer

A) some nuclei are moving fast enough to overcome the barrier to fusion 
B) there is a high probability some nuclei will strike each other head on 
C) the atoms are ionized 
D) thermal expansion gives the nuclei more room 
E) the uncertainty principle can be circumvented 
A) some nuclei are moving fast enough to overcome the barrier to fusion 
B) there is a high probability some nuclei will strike each other head on 
C) the atoms are ionized 
D) thermal expansion gives the nuclei more room 
E) the uncertainty principle can be circumvented

Question 18

Fission fragments usually decay by emitting:

Accepted Answer

A) alpha particles 
B) electrons and neutrinos 
C) positrons and neutrinos 
D) only neutrons 
E) only electrons 
A) alpha particles 
B) electrons and neutrinos 
C) positrons and neutrinos 
D) only neutrons 
E) only electrons

Question 19

In the uranium disintegration series:

Accepted Answer

A) the emission of a $\beta$- particle increases the mass number A by one and decreases the atomic number Z by one 
B) the disintegrating element merely ejects atomic electrons 
C) the emission of an $\alpha$ particle decreases the mass number A by four and decreases the atomic number Z by two 
D) the nucleus always remains unaffected 
E) the series of disintegrations continues until an element having eight outermost orbital electrons is obtained 
A) the emission of a $\beta$- particle increases the mass number A by one and decreases the atomic number Z by one 
B) the disintegrating element merely ejects atomic electrons 
C) the emission of an $\alpha$ particle decreases the mass number A by four and decreases the atomic number Z by two 
D) the nucleus always remains unaffected 
E) the series of disintegrations continues until an element having eight outermost orbital electrons is obtained

Question 20

The function of the control rods in a nuclear reactor is to:

Accepted Answer

A) increase fission by slowing down the neutrons 
B) decrease the energy of the neutrons without absorbing them 
C) increase the ability of the neutrons to cause fission 
D) decrease fission by absorbing neutrons 
E) provide the critical mass for the fission reaction 
A) increase fission by slowing down the neutrons 
B) decrease the energy of the neutrons without absorbing them 
C) increase the ability of the neutrons to cause fission 
D) decrease fission by absorbing neutrons 
E) provide the critical mass for the fission reaction

Exam 43: Energy From the Nucleus

In laser fusion, the laser light is:

To produce energy by fusion of two nuclei, the nuclei must:

Which one of the following represents a fission reaction that can be activated by slow neutrons?

When 236U fissions the fragments are:

The barrier to fission comes about because the fragments:

Nuclear fusion in stars produces all the chemical elements with mass numbers less than:

The binding energy per nucleon:

Separation of the isotopes of uranium requires a physical, rather than chemical, method because:

The energy released in a complete proton-proton cycle is about:

The barrier to fusion comes about because protons:

An explosion does not result from a small piece of 235U because:

Consider all possible fission events.Which of the following statements is true?

Most laser fusion projects attempt:

A nuclear reactor is operating at a certain power level, with its multiplication factor adjusted to unity.The control rods are now used to reduce the power output to one-half its former value.After the reduction in power the multiplication factor is maintained at:

Lawson's number is 1020 s.m-3.If the density of deuteron nuclei is 2 *1021 m-3 what should the confinement time be to achieve sustained fusion?

The energy supplied by a thermal neutron in a fission event is essentially its:

High temperatures are required in thermonuclear fusion so that:

Fission fragments usually decay by emitting:

In the uranium disintegration series:

The function of the control rods in a nuclear reactor is to:

Measurement

Motion Along a Straight Line

Vector

Motion in Two and Three Dimensions

Force and Motion I

Force and Motion II

Kinetic Energy and Work

Potential Energy and Conservation of Energy

Center of Mass and Linear Momentum

Rotation

Rolling, Torque, and Angular Momentum

Equilibrium and Elasticity

Gravitation

Fluids

Oscillations

Waves I

Waves II

Temperature, Heat, and the First Law of Thermodynamics

The Kinetic Theory of Gases

Entropy and the Second Law of Thermodynamics

Electric Charge

Electric Fields

Gauss Law

Electric Potential

Capacitance

Current and Resistance

Circuits

Magnetic Fields

Magnetic Fields Due to Currents

Induction and Inductance

Electromagnetic Oscillations and Alternating Current

Maxwells Equations; Magnetism of Matter

Electromagnetic Waves

Images

Interference

Diffraction

Relativity

Photons and Matter Waves

More About Matter Waves

All About Atoms

Conduction of Electricity in Solids

Nuclear Physics

Quarks, Leptons, and the Big Bang

Filters

When ²³⁶U fissions the fragments are:

An explosion does not result from a small piece of ²³⁵U because:

Lawson's number is 10²⁰ s.m^-3.If the density of deuteron nuclei is 2 *10²¹ m^-3 what should the confinement time be to achieve sustained fusion?