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How much kinetic energy must a deuterium ion (charge = 1.6 x 10 -19 C) have to approach within 10 -14 m of another deuterium ion? [k = 9 x 10 9 N-m 2 /C 2 and 1 MeV = 1.6 x 10 -13 J]. 30 KeV 50 KeV 70 KeV 140 KeV.
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How much kinetic energy must a deuterium ion (charge = 1.6 x 10-19 C) have to approach within 10-14 m of another deuterium ion? [k = 9 x 109 N-m2 /C2 and 1 MeV = 1.6 x 10-13 J] • 30 KeV • 50 KeV • 70 KeV • 140 KeV
How fast is an ion of deuterium moving if it is in a plasma with a temperature of 108 K? (kB = 1.38 x 10-23 J/K and mD = 2 x 1.66 x 10-27 kg) • 1.12 x 106 m/s • 0.93 x 105 m/s • 0.46 x 105 m/s • 2.32 x 104 m/s
One in 6500 water molecules (on average) contains a deuterium atom. If all the deuterium could be extracted from 1 m3 of water and then reacted, how much energy could be obtained? (Each D-D fusion liberates 3.65 MeV of energy, 1 MeV = 1.6 x 10-13 J) • 8.0 x 1010 J • 9.6 x 1010 J • 4.8 x 1011 J • 1.5 x 1012 J
The reason that a thermonuclear fusion reaction cannot be maintained in the oceans of the earth is because? • the temperature is not high enough. • the density is not high enough. • there is insufficient deuterium in the ocean. • the deuterium in the ocean is not radioactive.
The tokamak is used instead of the walls of a container to confine a plasma for nuclear fusion because, if the plasma touched the walls of a container, the nuclear fusion reaction would have to stop because? • the plasma would become cooler. • the plasma would melt the walls. • the walls would become radioactive. • the walls would not be strong enough to contain the plasma.
The formation of a star requires the consideration of the effects of gravity and the energy from nuclear reactions and a star will form only when both the temperature and density are sufficiently high. In the birth of a star, • gravity produces the initial required high temperature and density. • nuclear reactions produce the initial high temperature. • nuclear reactions produce the initial required high density. • nuclear reactions produce the initial required high temperature and density.
Which of the following is not true of neutrinos? • spinless • chargeless • massless • lepton
Which of the following particle reactions cannot occur? • p + p¯→ 2g • g + p→ n + po • po + n → K+ • p+ + p → K++ S+
Which of the following particle reactions cannot occur? • p + n → p + p + p¯ • n → p + e ¯ + ve ¯ • µ¯ → e ¯ + ve ¯ + vµ • p¯ → µ¯ + ve
The attractive force between protons and neutrons in the nucleus is brought about by the exchange of a virtual pi-meson (mp = 140 MeV/c2 ). Estimate the longest time a po can exist in accordance with the uncertainty principle DEDt = Ç. (Ç = 1.054 x 10-34 J-s, 1 eV = 1.6 x 10-19 J) • 3.3 x 10-18 s • 2.4 x 10-21 s • 4.7 x 10-24 s • 6.9 x 10-27 s
The pion (mp = 135 MeV/c2) is thought to be the particle exchanged in the nuclear force. What is the maximum range of this particle if its "time of existence" is as long as can be allowed by the uncertainty principle? (Ç = 1.054 x 10-34 J-s) • 1.2 x 10-15 m • 1.5 x 10-15 m • 2.0 x 10-15 m • 7.5 x 10-15 m
If two quarks in an anti-proton have the color anti-red and anti-blue, the third quark must have the color? • red. • blue. • anti-purple. • anti-green.
The spin of all quarks is? • 0. • 1/2. • 1. • 1/3 or 2/3.
The charge of some quarks or anti-quarks is? • 0. • 1/2 (1.6 x 10-19)C. • 1/3 (1.6 x 10-19) C. • 1 (1.6 x 10-19) C.
The strong force which acts between an electron and a quark is caused by the exchange of? • photons. • gluons. • gravitons. • W+, W-, and Z0 bosons.
Theoretical physicists have had the least success in combining which force with the electromagnetic force? • strong nuclear force • weak nuclear force • gravitational force • electrical Coulomb force
Theoretical physicists have had the greatest success in combining which force with the electromagnetic force? • strong nuclear force • weak nuclear force • gravitational force • the force caused by the exchange of gluons
Which of the following can only occur if the reproduction constant, K, exceeds 1? • Nuclear meltdown at a nuclear power plant • Explosive release of radioactivity and steam from a nuclear power plant • The explosion of a nuclear bomb • All of the choices require that K exceed 1
One result of thermal pollution in water near nuclear power plants in Canada is that? • roses can be grown near the plant in December. • the water contains toxic poisons. • the fish in the water are radioactive. • all the fish in the water are killed.
Which of the following will not influence the rate at which nuclear reactions will occur in a nuclear power plant where the fuel elements are a mixture of U-235 and U-238? • The presence of moderating material • The presence of control rods • The percentage of U-235 relative to U-238 • The percentage of the energy that is used to produce electricity
In a nuclear fission process involving the use of Pu-239 fuel, if the approximate average binding energy per nucleon in the product fragments is 8.5 MeV while that of the fuel atom is 7.7 MeV, what approximate net energy is released per fission? • 191 MeV • 239 MeV • 2030 MeV • 3850 MeV
The rate that an organism absorbs and circulates nutrient materials into its body can be measured by a nuclear technique involving which of the following? • neutron activation • tracing • scintillation counting • plasma confinement
In a fission reaction, a U-235 nucleus captures a neutron. What energy is released if the products are I-139, Y-95 and two neutrons? (atomic masses: U-235, 235.0439: I-139, 138.9350; Y-95, 94.9134; neutron, 1.00867; and 1 u x c2 = 931.5 MeV) • 123 MeV • 174 MeV • 199 MeV • 218 MeV
The water surrounding the fuel rods in a nuclear fission reactor serves what purpose(s)? • coolant • Moderator • both moderator and coolant • none of these
The K-ratio in a uranium fuel reactor is defined as the average number of neutrons from each fission event that will cause another event. In a well-functioning reactor, it is desired that the K-ratio have what value? • zero • 0.5 • 1.0 • 2.0
In a fusion reactor, the high temperature of the order of 108 K is required in order that what condition is met? • melt down the hydrogen fuel • strip the hydrogen atoms of their electrons • break the protons into their elementary particle sub-parts • overcome Coulomb repelling forces between protons
What characteristic is preferred in the elements contained in moderator materials when used in a nuclear fission reactor? • low atomic mass • metallic • non-metallic • high atomic mass
In a fission reaction, a U-235 nucleus captures a neutron. This results in the creation of the products I-137 and Y-96 along with how many neutrons? • 1 • 2 • 3 • 5
Assume that (i) the energy released per fission event of U-235 is 208 MeV and (ii) 30% of the nuclear energy released in a power plant is ultimately converted to usable electrical energy. Approximately how many fission events will occur in one second in order to provide the 2.0 kW electrical power needs of a typical home? (1 eV = 1.6 x 10-19 J) • 3 x 1010 fissions per sec • 2 x 1014 fissions per sec • 5 x 1018 fissions per sec • 3 x 1021 fissions per sec
Calculate the energy released in the following fusion reaction where reactants are Li-6 and a neutron; products are He-4 and H-3. (atomic masses: Li-6, 6.01512; neutron, 1.00867; He-4, 4.00260; H-3, 3.016031; also 1 u x c2 = 931.5 MeV) • 2.9 MeV • 4.8 MeV • 8.6 MeV • 17.2 MeV
In a nuclear fusion reactor, the Lawson criterion prescribes the necessary conditions, as related to density and confinement time of the plasma fuel, in order that the process produces a net power output. If the fuel density were doubled, by what factor would the required confinement time change? • 0.25 • 0.50 • 1.4 • 2.0
A capture by a target nucleus of uranium-235 is most apt to occur for which type of "bullet" particle? • low velocity alpha particle • low velocity proton • high velocity neutron • low velocity neutron
The moderator material in a nuclear fission reactor is intended to fulfill which of the following purposes? • absorb neutrons • create new neutrons • accelerate neutrons • decelerate neutrons
In a nuclear reactor which uses the fission process, which of the following is the most likely result in the event of a cooling system failure followed by a nuclear accident? • proliferation of plutonium fuel • accumulation of critical mass of fissionable material • spread of radioactive material into the environment • reduction of ozone in upper atmosphere
When comparing product nuclei to reactant nuclei in an exothermal nuclear fusion process, which has the greater binding energy per nucleon? • greater in product nuclei • greater in reactant nuclei • equal in both product and reactant nuclei • none of these
The advantage of a fission reactor when compared to a fusion reactor is which of the following? • the fuel is cheaper • there is less radioactive waste material • both cheaper fuel and less radioactive waste material • none of these
A plasma can be contained in a "magnetic bottle" because it has which of the following properties? • high temperature • liquid in form • made of charged particles • made of light elements
If a self-sustained controlled fusion reaction is to operate, a condition which must be met is that the fuel material be subjected to which of the following condition(s)? • confined for sufficient time period • have sufficiently high density • be at sufficiently high temperature • all of these
The mass of a proton is greater if it is in the nucleus of which of the following elements? • hydrogen • iron • uranium • krypton
It is possible to detect small amounts of arsenic in the hair of a deceased person by a technique involving which of the following? • Carbon-14 dating • nuclear fission • neutron activation • isotopic separation
According to the standard model, a quark and its anti-quark may have the same? • spin. • baryon number. • color. • all these things may be the same.
According to the standard model, there are some cases in which a quark and its anti-quark have the same? • charge. • baryon number. • strangeness. • all these things are always different.
The S+, S0, and S- all have strangeness of (-1). The collision of an anti-proton and a neutron may produce which of the following particles? • S- and S0 • S+ and anti-S0 • anti-S+ and S0 • anti-S- and S0
The S+, S0, and S- all have strangeness of (-1). The collision of a proton and a neutron to produce a S0 and an anti-S- cannot occur because it does not conserve? • strangeness. • charge. • baryon number. • all of the choices.
If a photon produces an electron-positron pair and one other particle, the other particle may be a(n)? • muon. • anti-neutrino. • neutrino. • photon.
Experimentally, strange particles can be produced in abundance but they decay relatively slowly. This occurs because strangeness? • is conserved in both their production and decay. • is conserved in their production but not in their decay. • is conserved in their decay but not in their production. • is not conserved in either their production or their decay.
The strangeness of an anti-proton is? • +1 • 0 • -1 • -2
If a negative muon decays to form an electron-positron pair and one other particle, the other particle may be a(n)? • positron. • anti-neutrino. • neutrino. • electron.
What quantity is conserved in the following reaction? n → p + e ¯ + ve ¯ • baryon number • charge • lepton number • all of the choices
What quantity is conserved in the following reaction?anti-n → p + e ¯ + ve ¯ • baryon number • charge • lepton number • all of the choices