PHYS 1020 exam 2
Atomic # equals
# of protons
Kyoto Protocol
(2005) controlling global warming by setting greenhouse gas emissions targets for developed countries
extra probability of getting cancer equation
1% (lifetime radiation/25 rems)
how many rems is someone typically exposed to in a year
100-1000 millirems
how many rems increase chance of cancer by 1%?
25 rems
how many rems is equal to one cancer?
2500 rems
how enriched does a nuclear bomb need to be
90%
nuclear fission
A nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
alpha decay
A nuclear reaction in which an atom emits an alpha particle consisting of two protons and two neutrons. This increases the atomic number by 2 and the mass number by 4.
ABM
Anti-Ballistic Missile; a defensive missile designed to shoot down incoming intercontinental ballistic missiles
isotope
Atoms of the same element that have different numbers of neutrons
what is nuclear fuel
Fuel derived from radioactive materials that give off energy
How was radioactivity discovered?
In 1896, the French scientist Henri Becquerel discovered the effects of radioactive decay by accident while studying a mineral containing uranium.
Geoengineering
Manipulation of earths climate system to counteract the effects of climate change caused by greenhouse gas emissions. i.e. make roots white so more sunlight is reflected, plant more trees, sulfur dioxide
MIRV
Multiple Indepentely Targetable Reentry Vehicle. Nuclear warheads that sit atop a variety of missiles in the US. inventory, and can hit multiple targets simultaneously
where was a nuclear bomb first tested?
New mexico
Three Mile Island
Nuclear Power Plant in Harrisburg, Penn. which failed, causing radiation to be admitted in the air worst nuclear accident in US pumps feeding in the cooling water failed human error and accidental partial meltdown radioactive steam started leaking out minor in physical effects, major in effects on opinion on nuclear energy
secret cities
Oakridge, Tennessee Los Alamos, New Mexico Hanford, Washington
uranium enrichment
Process of turning raw uranium into a reactor or bomb fuel uranium 238 + n -> uranium 239 because it turns into a lighter element, the mass disappears in the form of energy
Biological effects of radioactivity
Radiation Sickness ( > 100 REMS, 1 Sievert) Cancer ( Cancer risk depends on amount and type of exposure )
SALT 2 treaty
Strategic Arms Limitation Talks which limited the kinds and number of nuclear weaponry was never ratified
Mutually Assured Destruction (MAD)
The possession of second-strike nuclear capabilities, which ensures that neither of two adversaries could prevent the other from destroying it in an all-out war.
radioactivity
The spontaneous emission of radiation by an unstable atomic nucleus
uranium levels in nature
U-238 : 99.3% U-235 : .7%
START 1 treaty
U.S & USSR negotiation to reduce number of worldwide nuclear weapons
nuclear medicine
Uses radioactive materials either to image a patient's body or to destroy diseased cells
Keeling Curve
a graph made over the span of 50 years that shows the increase of carbon dioxide
carbon dating
a scientific method used to determine the age of an artifact carbon 14 is in every living thing, and the half life is known. so any thing that once was living can be dated by the amount of carbon that is left
What fraction of the world's nuclear weapons are controlled by the United States and Russia? Question options: a. Far more than half. b. About half. c. About one third. d. Far less than one third.
a. Far more than half.
The nuclear waste produced by a nuclear reactor consists mostly of Question options: a. fission fragments and plutonium b. fission fragments and uranium c. uranium and plutonium
a. fission fragments and plutonium
The element boron absorbs neutrons very effectively, without scattering them very much. In a nuclear reactor, boron would most likely be used as Question options: a. part of the control rods b. a moderator c. a coolant d. nuclear fuel
a. part of the control rods
Thorium-232 decays via the emission of an alpha particle. What does it decay into? Question options: a. radium-228 b. actinium-228 c. radon-230 d. radium-230
a. radium-228
Coolant's role in Nuclear Reactor
absorb heat and blow it away with steam
Control Rods' Role in a Nuclear Fission Reactor
absorb the neutrons stop the reaction
radioactivity and space
all probes sent to venus and mars lately are solar powered, but Jupiter, staturn, and pluto probes all us RTG: radio isotope thermoelectric generator
Intergovernmental Panel on Climate Change (IPCC)
an international group of scientists that evaluates scientific studies related to climate change to thoroughly and objectively assess the data
electromagnetic pulse (EMP)
atomic bomb shoots out a wave that creates currents
After alpha decay, the daughter nuclide will have an atomic mass number ____ amu lower than the parent a. 1 b. 2 c. 4 d. 6
b. 2
What sort of atomic bomb explosion produces the most fallout? Question options: a. An explosion deep underground. b. An explosion at the surface of the ground. c. An explosion at high altitude. d. An explosion in space
b. An explosion at the surface of the ground.
The atmosphere contains 1.0 x 1044 gas molecules, mostly nitrogen and oxygen. Using your results from problem 1, calculate the increase in carbon dioxide in the Earth's atmosphere from all of the coal that the United States burned in 2019. Express your answer in ppm (parts per million). (Note that ppm is the ratio of the number of carbon dioxide molecules to the total number of gas molecules, multiplied by 1 million). Question options: a. Less than 0.1 ppm b. Between 0.1 ppm and 1.0 ppm c. Between 1.0 ppm and 10.0 ppm d. More than 10.0 ppm
b. Between 0.1 ppm and 1.0 ppm
Combining one atom of carbon with two atoms of oxygen produces one molecule of carbon dioxide, along with 6.5 x 10-19 J of energy. In 2019, the United States burned enough coal to supply 1.1 x 1019 J of energy. Assuming that coal is roughly 100% carbon, how many molecules of carbon dioxide did the U.S. produce by burning coal in 2019? Question options: a. Less than 1036 molecules of carbon dioxide. b. Between 1036 and 1038 molecules of carbon dioxide. c. Between 1038 and 1040 molecules of carbon dioxide. d. More than 1040 molecules of carbon dioxide.
b. Between 1036 and 1038 molecules of carbon dioxide.
Which of the following would NOT reduce the greenhouse gas emissions of the United States? Question options: a. Discontinuing the use of coal, and using nuclear power to replace it. b. Discontinuing the use of nuclear power, and using natural gas to replace it. c. Discontinuing the use of natural gas, and using nuclear power to replace it. d. Discontinuing the use of coal, and using natural gas to replace it.
b. Discontinuing the use of nuclear power, and using natural gas to replace it.
Building a nuclear reactor or a nuclear bomb is possible because of which two properties of uranium? Question options: a. Most uranium is in the form of uranium-238, and when uranium-238 is bombarded with neutrons, it captures them. b. The fission of uranium-235 releases energy, and each fission produces 2 to 3 additional neutrons. c. Uranium is the heaviest naturally-occurring element, and it decays into lighter elements that are also radioactive. d. Uranium-238 is more abundant than uranium-235, and the half-life of uranium-238 is longer than the half-life of uranium-235.
b. The fission of uranium-235 releases energy, and each fission produces 2 to 3 additional neutrons.
The Canadian CANDU reactor uses natural uranium, with the moderator consisting of heavy water (deuterium oxide). If the moderator were removed, what would happen to the uranium in the reactor? Question options: a. Nothing. The reactor would continue to run normally. b. The fission reactions would stop. c. The fission reactions would increase out of control and the reactor would melt down. d. The reactor would blow up like an atomic bomb.
b. The fission reactions would stop.
Several years ago, Iran announced that it would begin enriching uranium up to a level of 60%. (This refers to uranium that is 60% uranium-235). What does this enrichment level correspond to? Question options: a. This level of enrichment is barely enough to run a nuclear reactor. b. This is far more enrichment than is necessary for a nuclear reactor, but less than what is necessary to build an atomic bomb. c. This is a high enough enrichment level to construct an atomic bomb.
b. This is far more enrichment than is necessary for a nuclear reactor, but less than what is necessary to build an atomic bomb.
Tritium is a radioactive isotope of hydrogen with a half-life of 12.5 years. Suppose you begin with a sample of 32 grams of tritium. After 50 years, how much tritium will you have left? Question options: a. There will be no tritium left; it will all decay away. b. You will have 2 grams of tritium left. c. You will have 8 grams of tritium left. d. You will have 16 grams of tritium left.
b. You will have 2 grams of tritium left.
Potassium-40 decays via the emission of a beta particle. What does it decay into? Question options: a. potassium-39 b. calcium-40 c. chlorine-36 d. argon-40
b. calcium-40
The total number of nuclear weapons in the world Question options: a. continues to grow and is larger now than it has ever been. b. reached a peak in the 1980s and has declined since then because of various treaties. c. reached a peak in the 1980s and has been roughly constant since then because of various treaties. d. has been roughly the same for the past 50 years.
b. reached a peak in the 1980s and has declined since then because of various treaties.
what should we do with nuclear waste?
bury it Yucca Mountain
A chest x-ray exposes you to roughly 40 millirems of radiation. How many chest x-rays would you need to get in order to increase your lifetime risk of cancer by approximately 1%? Question options: a. 6 b. 62 c. 625 d. 6250
c. 625
Biofuels such as wood generate carbon dioxide when they are burned, but biofuels are nonetheless considered a partial solution to climate change. Why? Question options: a. Because wood and other biofuels generate a lot of ash when they burn, and this ash in the atmosphere cools down the Earth. b. Because biofuels are more expensive than fossil fuels, so people will use less of them and generate less carbon dioxide. c. Because plants take carbon dioxide out of the air as they grow, and burning them puts the same amount of carbon dioxide back into the atmosphere, so they are "carbon neutral". d. Because wood and other biofuels contain only a small amount of carbon, so they do not generate very much carbon dioxide when burned.
c. Because plants take carbon dioxide out of the air as they grow, and burning them puts the same amount of carbon dioxide back into the atmosphere, so they are "carbon neutral".
Modern nuclear weapons programs enrich uranium using Question options: a. gaseous diffusion. b. particle accelerators. c. centrifuges
c. centrifuges
The main technical obstacle to building an atomic bomb using uranium during World War II was Question options: a. figuring out how to put together two pieces of uranium fast enough to create a critical mass. b. making a small enough atomic bomb to fit inside an airplane. c. separating out the uranium-235, which fissions, from the uranium-238, which does not fission.
c. separating out the uranium-235, which fissions, from the uranium-238, which does not fission.
After beta decay, the daughter nuclide will have an atomic mass that is _______ the parent nuclide. a. Higher than b. Lower than c. The same as
c. the same as
China syndrome worst case scenario for nuclear power
catastrophic coolant leak meltdown happens, gets way too hot, melts into the ground
how to enrich uranium
centrifuge
where was the first nuclear reactor made?
chicago
plutonium reactors
could blow up like a bomb fast neutrons are good, so no moderator needed
Which of the following is NOT true of nuclear fusion? Question options: a. It powers the sun. b. It has been harnessed for military purposes. c. It requires very high temperatures. d. It currently generates about 5% of United States energy production.
d. It currently generates about 5% of United States energy production.
The most intensely radioactive component of nuclear waste from nuclear reactors is Question options: a. uranium-235 that hasn't fissioned yet b. uranium-238 c. plutonium-239 produced when uranium-238 absorbs a neutron d. fission fragments, i.e., radioactive isotopes produced when uranium-235 fissions
d. fission fragments, i.e., radioactive isotopes produced when uranium-235 fissions
The United States and the Soviet Union signed a treaty in the early 1960s to stop testing atomic bombs in the atmosphere. The main motivation for this treaty was Question options: a. to reduce the stockpile of nuclear weapons. b. to reduce the risk of accidental nuclear war. c. to stop other countries from observing how atomic bombs worked. d. to stop the radioactive fallout generated by atmospheric testing.
d. to stop the radioactive fallout generated by atmospheric testing.
moderator examples in nuclear fission reactor
deuterium ("heavy water") carbon -> graphite
fusion power
energy of the future limitless clean power
disadvantages of nuclear power
expensive to build produces nuclear waste dangerous use a reactor to make a bomb
how does the particle change after beta decay?
goes up 1 atomic number
food radiation
kills the growth of organisms such as molds, bacteria, and yeasts cobalt 60
SALT 1 treaty
limited antiballistic missles (defensive weapons) limit to 1 antiballistic missle
greenhouse gases
methane, carbon dioxide, water vapor
missles vs bombs
missles cannot be deactivated missles are a little destabalizing bombers can just come back
blast
mushroom cloud
is radioactivity contagious?
no only if the radioactive material gets transferred to someone else
advantages of nuclear power
no fossil fuels -> green energy source no CO2 emissions good bridge from fossil fuels to renewables
chernobyl
nuclear power plant in Russia that had an explosion in 1986 & released radioactive materials into the air worst nuclear accident on history of planet control rods had a graphite tip that increased fusion instead of slowing it down positive voide coefficient increased rate of fission no containment vessle steam explosion, exploded radioactive waste estimated 4,000 deaths
tactile nuclear weapons
nuclear weapons to be used in war on the battlefield, US finds out after the Cuban missile crisis that SU sent these to Cuba and gave them permission to use them if US invaded
mass # equals
protons + neutrons
gamma decay
radioactive decay by emission of a gamma ray (high energy photon)
beta decay
radioactive decay in which an electron is emitted. a neutron turns into a proton
fallout
radioactive particles dispersed by a nuclear explosion
nuclear waste
radioactive waste material produced by nuclear power plants Pu- 239 fission products fission fragments
radon 222
second leading cause of lung cancer
Fukishima Daiichi Nuclear Power Plant
second worst nuclear accident earthquake and subsequent tsunami reactor shut down, and the gasoline powered backup generator continued to circle coolant earthquake shut reactor down, tsunami flooded pipes caused a meltdown there was a containment vessel -> no immediate deaths
Moderator's Role in a Nuclear Fission Reactor
slow down neutrons scatter neutrons
Radiation Hormesis Theory
small doses of radiation actually decrease the chance of getting cancer.
nuclear winter
the expected freeze that would occur in the Earth's climate from the fallout of smoke and dust in the event nuclear weapons were used, blocking out sunlight and destroying the plant and animal life that survived the original blast
why wouldn't a dirty bomb happen
the people closest to the bomb would receive radiation so concentrated that they would die in a fraction of a second, so the terrorist would die
carbon dating and ATF (alcohol)
there should be radioactivity in alcohol, because it should be made from things that were once living not allowed to use petroleum
fireball
thermal energy traveling from the nuclear weapon
submarines for nuclear
ultimate stabilizing can just sit at bottom of ocean
fuel for nuclear reactor
uranium or plutonium
how can we lower CO2 emissions?
use renewable energy/more efficient energy (I.e. hydro, wind, solar, nuclear) carbon tax - put tax on carbon emissions geoengineering
greenhouse effect
warming that results when solar radiation is trapped by the atmosphere earth absorbs visible light and releases it as infrared
rems
way to measure radioactivity
