Question 1

Which has the smaller critical mass; U-235 that releases 2.5 neutrons per fission, or Pu-239 that releases 2.7 neutrons per fission?

Accepted Answer

A) U-235 
B) Pu-239 
C) both would have the same critical mass. 
A) U-235 
B) Pu-239 
C) both would have the same critical mass.

Question 2

U-235 and Pu-239 are both

Accepted Answer

A) radioactive isotopes. 
B) fissionable isotopes. 
C) heavier than lead. 
D) all of the above 
E) none of the above 
A) radioactive isotopes. 
B) fissionable isotopes. 
C) heavier than lead. 
D) all of the above 
E) none of the above

Question 3

Plutonium is extremely rare in natural ore deposits because it

Accepted Answer

A) is artificially created. 
B) is chemically inert. 
C) is a gas at room temperature. 
D) has a tiny half-life compared with the age of Earth. 
E) none of the above 
A) is artificially created. 
B) is chemically inert. 
C) is a gas at room temperature. 
D) has a tiny half-life compared with the age of Earth. 
E) none of the above

Question 4

Plutonium is radioactively toxic

Accepted Answer

A) in any form. 
B) although less toxic than radium. 
C) both of these 
D) neither of these 
A) in any form. 
B) although less toxic than radium. 
C) both of these 
D) neither of these

Question 5

What does a breeder reactor "breed?"

Accepted Answer

A) more energy output than energy input 
B) fissionable isotopes from a non-fissionable isotopes 
C) more mass than it begins with 
D) all of the above 
E) none of the above 
A) more energy output than energy input 
B) fissionable isotopes from a non-fissionable isotopes 
C) more mass than it begins with 
D) all of the above 
E) none of the above

Question 6

Earth's interior is warmed by ________ and Earth's surface is warmed by ________.

Accepted Answer

A) radioactive processes; fusion in the Sun 
B) fission; fossil fuels 
C) volcanoes; solar energy 
D) terrestrial radiation; terrestrial radiation 
A) radioactive processes; fusion in the Sun 
B) fission; fossil fuels 
C) volcanoes; solar energy 
D) terrestrial radiation; terrestrial radiation

Question 7

The term critical mass refers to the least amount of mass that can

Accepted Answer

A) sustain a chain reaction. 
B) squelch a chain reaction. 
C) explode when rapidly brought against a neighboring piece. 
D) none of the above 
A) sustain a chain reaction. 
B) squelch a chain reaction. 
C) explode when rapidly brought against a neighboring piece. 
D) none of the above

Question 8

Compared with a neutron bouncing off a carbon nucleus, a neutron bouncing off an iron nucleus loses

Accepted Answer

A) less speed. 
B) more speed. 
C) the same amount of speed. 
A) less speed. 
B) more speed. 
C) the same amount of speed.

Question 9

The kinetic energy of fission fragments in a nuclear reactor

Accepted Answer

A) superheats water and produces steam. 
B) converts to gamma-ray radiation. 
C) becomes radioactive pollution. 
D) converts directly to electricity. 
E) none of the above 
A) superheats water and produces steam. 
B) converts to gamma-ray radiation. 
C) becomes radioactive pollution. 
D) converts directly to electricity. 
E) none of the above

Question 10

Compared with protons, neutrons are more effective nuclear bullets in nuclear reactions since they have

Accepted Answer

A) slightly greater mass than a proton. 
B) no charge. 
C) a wider cross-section than a proton. 
D) all of the above 
E) none of the above 
A) slightly greater mass than a proton. 
B) no charge. 
C) a wider cross-section than a proton. 
D) all of the above 
E) none of the above

Question 11

Sustained energy output by fusion is a daily occurrence in

Accepted Answer

A) military installations. 
B) breeder reactors. 
C) the Sun. 
D) Earth's interior. 
A) military installations. 
B) breeder reactors. 
C) the Sun. 
D) Earth's interior.

Question 12

Control is maintained in a nuclear reactor by control rods that

Accepted Answer

A) absorb excess neutrons. 
B) emit fast neutrons. 
C) both of these 
D) neither of these 
A) absorb excess neutrons. 
B) emit fast neutrons. 
C) both of these 
D) neither of these

Question 13

Compared with the sum of isolated-nucleon masses, their collective mass in a composite nucleus is

Accepted Answer

A) more. 
B) less. 
C) the same. 
A) more. 
B) less. 
C) the same.

Question 14

Between the processes of nuclear fission and fusion, radioactive by-products are more characteristic of nuclear

Accepted Answer

A) fission. 
B) fusion. 
C) both of these 
D) neither of these 
A) fission. 
B) fusion. 
C) both of these 
D) neither of these

Question 15

If gold were used as nuclear fuel, it would be best

Accepted Answer

A) fused. 
B) fissioned. 
C) either of these 
A) fused. 
B) fissioned. 
C) either of these

Question 16

Iron is a poor choice of nuclear fuel because it releases

Accepted Answer

A) energy only when fused. 
B) energy only when fissioned. 
C) no energy when fused or fissioned. 
A) energy only when fused. 
B) energy only when fissioned. 
C) no energy when fused or fissioned.

Question 17

Compared with the energy produced by fissioning a gram of uranium, the energy produced by fusing a gram of deuterium is

Accepted Answer

A) more. 
B) less. 
C) the same. 
A) more. 
B) less. 
C) the same.

Question 18

What is the central equation of mass-energy equivalence?

Accepted Answer

A) W = Fd 
B) KE = ½ mv2 
C) m = F/a 
D) E = mc2 
A) W = Fd 
B) KE = ½ mv2 
C) m = F/a 
D) E = mc2

Question 19

The possible fate of a neutron in ordinary uranium metal is to

Accepted Answer

A) cause fission of U-235 if present. 
B) escape the metal. 
C) be absorbed by U-238 without causing fission. 
D) all of the above 
E) none of the above 
A) cause fission of U-235 if present. 
B) escape the metal. 
C) be absorbed by U-238 without causing fission. 
D) all of the above 
E) none of the above

Question 20

Detonation of a fission-type uranium bomb begins by

Accepted Answer

A) splitting uranium. 
B) pressing together pieces of uranium. 
C) igniting a small conventional bomb. 
D) all of the above 
E) none of the above 
A) splitting uranium. 
B) pressing together pieces of uranium. 
C) igniting a small conventional bomb. 
D) all of the above 
E) none of the above

Exam 34: Nuclear Fission and Fusion

Which has the smaller critical mass; U-235 that releases 2.5 neutrons per fission, or Pu-239 that releases 2.7 neutrons per fission?

U-235 and Pu-239 are both

Plutonium is extremely rare in natural ore deposits because it

Plutonium is radioactively toxic

What does a breeder reactor "breed?"

Earth's interior is warmed by ________ and Earth's surface is warmed by ________.

The term critical mass refers to the least amount of mass that can

Compared with a neutron bouncing off a carbon nucleus, a neutron bouncing off an iron nucleus loses

The kinetic energy of fission fragments in a nuclear reactor

Compared with protons, neutrons are more effective nuclear bullets in nuclear reactions since they have

Sustained energy output by fusion is a daily occurrence in

Control is maintained in a nuclear reactor by control rods that

Compared with the sum of isolated-nucleon masses, their collective mass in a composite nucleus is

Between the processes of nuclear fission and fusion, radioactive by-products are more characteristic of nuclear

If gold were used as nuclear fuel, it would be best

Iron is a poor choice of nuclear fuel because it releases

Compared with the energy produced by fissioning a gram of uranium, the energy produced by fusing a gram of deuterium is

What is the central equation of mass-energy equivalence?

The possible fate of a neutron in ordinary uranium metal is to

Detonation of a fission-type uranium bomb begins by

About Science

Newtons First Law of Motion: Inertia

Linear Motion

Newtons Second Law of Motion

Newtons Third Law of Motion: Action and Reaction

Momentum

Energy

Rotational Motion

Gravity

Projectile and Satellite Motion

Atomic Nature of Matter

Solids

Liquids

Gases and Plasmas

Temperature, Heat, and Expansion

Heat Transfer

Change of Phase

Thermodynamics

Vibrations and Waves

Sound

Musical Sounds

Electrostatics

Electric Current

Magnetism

Electromagnetic Induction

Properties of Light

Color

Reflection and Refraction

Light Waves

Light Emission

Light Quanta

The Atom and the Quantum

Atomic Nucleus and Radioactivity

Special Theory of Relativity

General Theory of Relativity

Systems of Measurement

Filters

Earth's interior is warmed by and Earth's surface is warmed by .