Questions
1 Fission reactions in an atomic bomb proceed primarily by....
a
... spontaneous disintegration of nuclei.
b
... high temperature collisions between nuclei.
... disintegration
of nuclei stimulated by neutrons.
d
... high velocity collisions between nuclei.
2 Heavy element fission reactions are unimportant in stars
because....
a
... there is insufficient energy is released per reaction.
... too little fuel
is available.
c
... the temperature is too high.
d
... stars are too large.
3 Fusion reactors would be a desirable source of power because....
a
... they give off no undesirable waste products.
b
... the fuel is cheap.
c
... the reaction is very energetic.
... all of these.
4 One advantage of fission reactions as a source of energy
when compared to other means of generation is....
a
... plentiful, cheaper fuel.
b
... reactions that are safe without supervision.
c
... the production of little dangerous waste material.
... the power station
can be put where the power is needed.
5 The explosive power of an atomic bomb comes from....
a
... a combustion reaction.
b
... a TNT explosion.
... a fission reaction.
d
... a fusion reaction.
6 A chain reaction occurs when....
... one of the fragments of fission stimulates another nucleus to fission.
b
... one of the fragments of fission itself fissions.
c
... several nuclei simultaneously fission.
d
... any ordinary chemical reaction occurs.
7 A necessary condition for the occurrence of an explosive
fusion reaction in an appropriate fuel is....
... high temperature.
b
... critical mass.
c
... proper catalyst.
d
... free neutrons.
8 Which type of reaction is most easily controlled?
a
Fusion
Fission
c
The burning of TNT
d
None of the above can be controlled.
9 We know that uranium cannot be the main source of energy
for the sun since....
... the sun contains
no uranium.
b
... the sun contains some uranium, but too little.
c
... neutrons necessary for this nuclear reaction are missing
in the sun.
d
... the temperature is too high for this reaction to take place.
10 Natural radioactivity involves which of the following?
a
The absorption of mass/energy by an orbital electron.
b
The emission of mass/energy by an orbital electron.
c
The absorption of mass/energy by an atomic nucleus.
The emission of mass/energy
by an atomic nucleus.
11 Which of the following may sometimes be described as a
chain reaction?
a
Burning gunpowder.
b
Alpha decay.
c
Fusion.
Fission.
12 One disadvantage of fusion reactions as a source of energy
is that they...
... are not easily
controlled.
b
... produce dangerous waste material.
c
... are not easy to understand.
d
... are too destructive.
13 Uranium is an undesirable long term commercial source of energy, primarily because of....
a
... the danger of catastrophic accidents.
b
... the dangerous by products produced.
... the relative
scarcity of available ore.
d
... the concentration of ores in the Middle East.
14 Fission reactions are not the principle source of energy
for stars because....
a
... they don't produce very much energy per reaction.
b
... undesirable by-products are also produced.
c
... the temperature in a star is too great.
... the appropriate
elements are too scarce in ordinary stars.
15 Which of the following is not a current problem or disadvantage
for current nuclear reactors?
Scarce fuel
b
Difficult to control reactions.
c
Possible leakage of radioactive waste into the atmosphere
d
Dangerous waste products
16 A fission chain reaction depends upon....
... the release
of neutrons at each fission.
b
... very high temperatures.
c
... a light chemical element for fuel.
d
... a source of control for the reactions.
17 The energy released in one single uranium fission reaction
is equal to the energy released by burning....
a
... 1000 TNT atoms.
...10,000,000 TNT
atoms.
c
... one gram of TNT.
b
...one kg of TNT.
18 When the critical mass of uranium is exceeded, the chain
reaction....
... occurs
explosively.
b
... continues at the same rate.
c
... ceases.
d
... slows to the ordinary rate.
19 Which of the following nuclear reactions is associated
with a chain reaction?
a
44H --> 4He
238U
+ n --> 239U
c
238U --> 234Th
+ a + g
d
None of the above
20 A quantity of uranium greater than the critical mass is
necessary to....
... make a bomb.
b
... generate heat by fission reactions.
c
... release neutrons by fission.
d
... all of the above.
21 The fuel source of the Sun is....
a
... carbon
... hydrogen.
c
... helium.
d
... unknown.
22 A mushroom cloud is associated with....
a
... all nuclear bomb detonations.
b
... hydrogen bomb detonations only.
c
... only nuclear bomb detonations.
... nuclear bomb
detonations in the lower atmosphere.
23 A breeder reactor....
... produces new
fuel while producing energy.
b
... is used to manufacture natural gas.
c
... is a fusion type reactor.
d
... is technically impossible.
24 The energy produced in a fusion reactor....
a
... can be controlled by limiting the number of neutrons released
during each fusion.
b
... can be limited by increasing the temperature.
... can be controlled
by varying the temperature and plasma density.
d
... cannot be controlled.
25 A nuclear bomb type explosion cannot occur accidentally
in a thermal nuclear power plant because....
a
... there is not enough uranium present.
b
... of all the safeguards built into the plant.
c
... the operators will flood the building before they let it
happen.
... the uranium fuel
is not pure enough.