Week 11-15 Test 3

Gas centrifuge separation, a method used for separating 235U from 238U, works because of a) the fact that both these nuclei respond to (or feel) the strong nuclear force. b) the difference in electrical charge of the two nuclei. c) the fact that both these nuclei are radioactive. d) the difference in the masses of the two nuclei.

d

In a nuclear reactor, the control rods must be able to a) absorb 235U. b) absorb 238U. c) slow neutrons down without absorbing them. d) absorb neutrons. e) remove the heat from the fissioning uranium.

d

In quantum theory, "entanglement" refers to a)the fact that a particle can get trapped in the electric field of another particle. b)the communication that occurs when one particle sends an electromagnetic wave to another. c) the forces that two particles can exert on each other even when they are separated. d)the intermixing of two particles' psi fields with each other. e) the spreading out of a single particle's psi field over a region of space.

d

Radon-222 alpha decays to Polonium-218 , and the half-life is 4 days. If you start with 4 grams of Radon-222, how much will you have after 16 days? a) 0 g b) 0.5 g c) 1 g d) 0.25 g

d

Some rocks are fluorescent when you shine ultraviolet light on them. What does this mean? a) These rocks are from a different planet b) They absorb the ultraviolet light. Once the ultraviolet light is removed, they will put out light of a different color (blue, orange, yellow, etc). c) They absorb visible light and put out ultraviolet light, but they only do this while the visible light is shining on them. d) They absorb the ultraviolet light and put out light of a different color (like blue, orange, or yellow). But they only do this for as long as the ultraviolet light shines on them.

d

The U.S. originally started the fission bomb project because a) it seemed like it would be fun. b) it thought it would need it against Japan c) its military wanted the biggest bomb possible. d) it was afraid that Germany was developing it. e) it wanted to threaten Russia with it after the war.

d

The forces that hold the nucleus together a) act over only very short distances. b) are much stronger than electromagnetic forces. c) are attractive, that is, they pull in the inward direction. d) all of the above. e) none of the above

d

What do you get when helium-4 and carbon-12 fuse? a) beryllium-8 b) neon-10 c) tritium d) oxygen-16

d

What does a thermonuclear reaction typically refer to? a) something really hot b) fission c) radioactivity d) fusion

d

When an atom undergoes a "quantum jump" into a lower-energy state, the atom a) emits an electron. b) absorbs an electron. c) absorbs a photon. d) emits a photon.

d

Which of the following thought of the idea that the psi-field represents probabilities? a) Einstein b) Newton c) Schroedinger d) Born e) Planck

d

Why do modern glow in the dark toys glow? a) because they are fluorescent b) because they are photofluorescent c) because they are painted green d) because they are phosphorescent

d

A "critical mass" is need for a chain reaction because a) if the mass is too large, the density will be too high to sustain a chain reaction. b) if the mass is too small, there will not be enough uranium to start the reaction. c) if the mass is too large, the temperature will get too high and the entire mass will blow up without fissioning. d) if the mass is too small the temperature achieved during fission will be too low to sustain the reaction. e) if the mass is too small, too many neutrons will leak out without causing fission.

e

If you start with 6 grams of pure carbon-14, how much is left after 18000 years? Assume the halflife of carbon-14 is 6000 years a) 1.5g b) 3g c) 0g d) .375g e) .75g

e

One difference between electrons and photons is a) photons obey quantum theory, while electrons obey Newtonian physics. b) electrons are particles while photons are waves. c) electrons are grumpy but photons are cheerful. d) electrons are particles, while photons can be either waves or particles. e) electrons have a rest mass while photons do not.

e

The percentage of 235U, as a fraction of the total uranium content, in a uranium fission bomb is closest to a) 1 percent. b) 5 percent. c) 20 percent. d) 50 percent. e) 90 percent.

e

What is the atomic number of deuterium?

1

What is the mass number of tritium?

3

How many neutrons are in one atom of oxygen-17 ?

9

Uranium's atomic number is 92 What is the atomic number of plutonium?

94

Approximately when was fission discovered? a) 1930 - 1950 b) 1910 - 1930 c) 1890 - 1910 d) 1950 - 1970

a

Continuing the preceding question, the percentage of 235U present in natural uranium is closest to a) 1 percent. b) 5 percent. c) 20 percent. d) 50 percent. e) 99 percent.

a

How does a hydrogen bomb compare in explosive size to a plutonium bomb? a) the hydrogen bomb has more explosive power than a plutonium bomb b) They hydrogen bomb and the plutonium bomb have about the same explosive power c) The plutonium bomb has more explosive power than the hydrogen bomb

a

How long after the Trinity Test was the first atomic bomb dropped on Hiroshima? a) about 3 weeks b) about 3 years c) about 3 days d) about 3 months

a

In order for a substance to sustain a fission chain reaction, one important condition is that a) each fissioning nucleus must release a sufficient number of neutrons. b) energy must be continually supplied from the outside c) each fissioning nucleus must release a sufficient number of alpha-particles. c) the nuclei must collide with enough energy to overcome the electrical repulsion between them.

a

In three dimensions, the quantum state in figure 13.18(c) is best described as having the shape of a) a dumbbell (not sure what a dumbbell is? go to Amazon.com and search for dumbbells) b) a doughnut c) a sphere d) a dumbbell and a doughnut

a

Radium-228 beta decays. What is the daughter nucleus? (Radium is element 88) a) Actinium-228 b) Thorium-232 c) Francium-228 d) Radon-224

a

Strontium-90 has a half life of 30 years. If we start with 10 grams, how long until we have only 1.25 grams? a) 90 years b) 150 years c) 120 years d) 60 years

a

The two nuclei that can sustain a nuclear chain-reaction are a) 235U and plutonium b) 238U and plutonium c) thorium and 235U d) thorium and plutonium

a

Which of the following scientists was not associated either relativity or quantum mechanics? a) Joule b) Schroedinger c) Planck d) Einstein e) de Broglie

a

Why do bones appear white on X-Rays? a) Because the bones stop the X-rays reaching the photographic film b) Because the bones let lots of X-rays reach the photographic film c) Because the film goes white when it is exposed to X-rays d) Because bones are white

a

Would you expect radon (atomic number 86) to be radioactive? a) Yes b) No

a

About how much of Arkansas's electricity comes from renewable sources? a) 30% b) 5% c) 50% d) 12%

b

Approximately when were Marie and Pierre Currie working on discovering radium? a) at the beginning of the 1800s b) at the beginning of the 1900s c) around 1850 d) around 1950

b

As a particle's uncertainty in position gets smaller, its uncertainty in speed a) must remain unchanged. b) must increase enough to satisfy the uncertainty principle. c) must decrease enough to satisfy the uncertainty principle.

b

How many protons and neutrons are in this nucleus? Uranium 235 92 a) 92 protons and 235 neutrons b) 92 protons and 143 neutrons c) 235 protons and 92 neutrons d) 92 protons and 327 neutrons

b

If a microscopic particle's uncertainty in speed is reduced, a)its uncertainty in position must remain unchanged. b)its uncertainty in position must increase enough to satisfy the uncertainty principle. c)its uncertainty in position must decrease enough to satisfy the uncertainty principle.

b

Lisa Meitner was a) one of the discoverers of radioactivity. b) one of the discoverers of nuclear fission. c) a leader in developing the world's first nuclear reactor. d) one of the discoverers of nuclear fusion.

b

Naturally occurring uranium is mostly a) 235U b) 238U c) 14U d) 233U

b

Polonium-209 alpha decays. What is the daughter nucleus? (Polonium is element 84) a) mercury-207 b) lead-205 c) astatine-209 d) radon-213

b

Quantum theory was developed a) almost in its entirety by Max Planck. b) by Planck, Schroedinger, Einstein, and many other scientists. c) almost in its entirety by Albert Einstein. d) almost in its entirety by Erwin Schroedinger. e) in its entirety by Planck, Schroedinger, and Einstein.

b

Say if the following nuclear reaction is energetically favorable (which means that energy is given off: nuclE --> thermE + radE) fusion reaction a) Yes, this is energetically favorable b) No, this is not energetically favorable

b

Suppose that you fission a sulfur nucleus, 32S, into two fragments. Referring to the nuclear energy graph, is this process energetically favorable or unfavorable? a) favorable, because this process proceeds from lower to higher energy on the curve. b) unfavorable, because this process proceeds from lower to higher energy on the curve. c) unfavorable, because this process proceeds from higher to lower energy on the curve. d) favorable, because this process proceeds from higher to lower energy on the curve.

b

What color is laser light? a) white b) it can be any color at all, depending on what atoms you excite within the laser itself. c) red d) green

b

What radioactive substance is typically in ionization chamber smoke detectors? a) polonium b) americium c) radon d) plutonium

b

Which of the following would not be considered renewable? a) biofuel b) nuclear (uranium and plutonium) c) geothermal d) wind e) hydroelectric f) all of these answers are renewable

b

Who discovered radioactivity? a) Marie Curie b) Henri Becquerel c) Wilhelm Roentgen d) Albert Einstein

b

Among the following list, the largest single source of radiation in the environment is a) medical diagnosis b) cosmic rays c) radon d) nuclear power plants e) fallout

c

Are X-rays visible? a) Only at night b) Yes c) No d) Sometimes

c

Enrico Fermi was a) the inventor of radiation therapy. b) the head of the program to develop the world's first fission bomb. c) the head of the program to develop the world's first nuclear reactor. d) the discoverer of nuclear fission.

c

How many atomic bombs have actually been dropped by nations at war (on their opponents)? a) none b) one c) two d) three

c

How many nobel prizes did Marie Curie win? a) zero b) one c) two d) three

c

Hydrogen-3 ( 3H) will radioactively decay into helium-3 ( 3He). Which type of decay is this? a) gamma decay b) alpha decay c) beta decay d) delta decay

c

Suppose that you fission a lead nucleus, 207Pb, into two fragments. Referring to the nuclear energy graph, is this process energetically favorable or unfavorable? a) unfavorable, because this process proceeds from lower to higher energy on the curve. b) unfavorable, because this process proceeds from higher to lower energy on the curve. c) favorable, because this process proceeds from higher to lower energy on the curve. d) favorable, because this process proceeds from lower to higher energy on the curve.

c

The atomic bomb is based on a) a chemical reaction. b) nuclear fusion. c) nuclear fission. d) radioactive decay.

c

The difference between the "ground state" and an "excited state" for a hydrogen atom is a) the excited state has more energy. b) the atom can radiate when it is in an excited state, but not when it is in a ground state. c) both of the above. d) none of the above

c

The spectrum of the hydrogen atom differs from the spectrum of the helium atom due to a) their different energy levels. b) the different frequencies of their emitted photons. c) both of the above. d) neither of the above.

c

Two different isotopes of the same element have a) different numbers of protons but the same number of neutrons b) different chemical properties c) the same number of protons, but different numbers of neutrons. d) different numbers of electrons. e) different numbers of both protons and neutrons

c

Uranium is one possible fission-reactor fuel. Another is a) radium, obtained by the enrichment of naturally-occuring radium. b)thorium, produced from the isotope 238U that is present in reactor fuel. c) plutonium, produced from the isotope 238U that is present in reactor fuel.

c

What is in the orange fiesta ware that makes it radioactive? (orange plate) a) bismuth b) astatine c) uranium d) radium e) plutonium

c

What is the daughter nucleus when 212Bi alpha decays? a) 216At b) 212Pb c) 208Tl d) 212Po

c

What type of nuclear reaction is the breaking up of one big nucleus into several smaller nuclei? a) Fusion b) Radioactivity c) Fission

c

What type of nuclear reaction is the spontaneous breakup of a nucleus, sending out either alpha particles or beta particles? a) Fission b) Fusion c) Radioactivity

c

Which famous scientist sent a letter to Franklin Roosevelt in 1939, warning him that nuclear fission might lead to a new and powerful kind of bomb? a) Bohr b) Compton c) Einstein d) Fermi

c

Which of the following works best for fissioning a uranium nucleus? a) Hit it with another uranium nucleus. b) Hit it with a proton. c) Hit it with a neutron.

c

Why are X-rays dangerous? a) They are loud and can damage your hearing b) They get stuck in your clothes c) They can damage cells in your body d) They are very bright and can damage your eyesight

c