Exam 1 Flashcards
1
Q
"Smart Rocks" are considered for ( ) geologic dating ( ) ballistic missile defense ( ) nuclear power ( ) solar power
A
ballistic missile defense
2
Q
One watt is equivalent to: ( ) one joule/sec ( ) one coulomb/sec ( ) one calorie/sec ( ) one horsepower
A
one joule/sec
3
Q
The asteroid that killed the dinosaurs exploded because
( ) it was made of explosive material
( ) it was made out of U-235
( ) it got very hot from the impact
( ) it didn’t explode. It knocked the Earth out of its normal orbit
A
it got very hot from the impact
4
Q
Kinetic energy can be measured in: ( ) watts ( ) calories ( ) grams ( ) amperes
A
calories
5
Q
Which of the following statements is true?
( ) Energy is measured in joules and power is measured in calories
( ) Power is energy divided by time
( ) Batteries release energy but TNT releases power
( ) Power signifies a very large value of energy
( ) all of the above
A
Power is divided by time
6
Q
Next to each of these mark whether it is a unit of energy (E) or power (P) horsepower \_\_\_\_\_ kilowatt-hour \_\_\_\_\_ watt \_\_\_\_\_ calorie \_\_\_\_\_
A
P
E
P
E
7
Q
Hybrid vehicles run on: ( ) electric and solar power ( ) solar power and gasoline ( ) electric power and gasoline ( ) nuclear power and gasoline
A
Electric power and gasoline
8
Q
What is the main reason that hydrogen-driven automobiles have not replaced gasoline ones?
( ) Hydrogen is too expensive
( ) Hydrogen is too difficult to store in an automobile
( ) Hydrogen is radioactive, and the public fears it
( ) Hydrogen mixed with air is explosive
A
Hydrogen is too difficult to store in an automobile
9
Q
Compared to an equal weight of gasoline, uranium-235 can deliver energy that is greater by a factor of (pick the closest) ( ) 2200 ( ) 25,000 ( ) one million ( ) one billion
A
one million
10
Q
Which of the following contains the most energy per gram? ( ) TNT ( ) chocolate chip cookies ( ) battery ( ) uranium
A
Chocolate chip cookies
11
Q
Compare the energy in a kilogram of gasoline to that in a kilogram of flashlight batteries:
( ) the gasoline has about 400 times as much energy
( ) the gasoline has about 10 times as much energy
( ) the gasoline has about 70 times less energy
( ) they cannot be honestly compared, since one stores power and the other stores energy
A
The gasoline has about 10 times as much energy
12
Q
Which is least expensive---for the same energy delivered? ( ) coal ( ) gasoline ( ) natural gas ( ) AAA batteries
A
Coal
13
Q
The kinetic energy of a typical 1-gram meteor is approximately equal to the energy of ( ) 10 grams of TNT ( ) 150 grams of TNT ( ) 1/100 grams of TNT ( ) 10 grams of gasoline
A
150 grams of TNT
14
Q
Coal reserves in the United States are expected to last for ( ) hundreds of years ( ) three or four decades ( ) 72 years ( ) less than a decade
A
Hundreds of years
15
Q
A limitation for all electric automobiles is
( ) low energy density per battery
( ) batteries explode more readily than gasoline
( ) electric energy is not useful for autos
( ) electric motors are less efficient than gasoline motors
A
Low energy density per battery
16
Q
Solar power is about (mark all that are correct): ( ) 1 Watt per square meter ( ) 1 kW per square meter ( ) 1 megawatt per square km ( ) 1 gigawatt per square km
A
1 kW per square meter
1 gigawatt per square km
17
Q
The efficiency of inexpensive solar cells is closest to ( ) 1% ( ) 12% ( ) 65% ( ) 100%
A
12%
18
Q
A human, running up stairs, can briefly use power of approximately ( ) 0.01 horsepower ( ) 0.1 horsepower ( ) 0.2 horsepower ( ) 1 horsepower
A
1 horsepower
19
Q
A 12-oz can of soft drink (not the "diet" or "lite" kind) contains about ( ) 10 Calories ( ) 50 Calories ( ) 150 Calories ( ) 2000 Calories
A
150 calories
20
Q
A large nuclear power plant delivers energy of about ( ) 1 megawatt ( ) 1 gigawatt ( ) 100 gigawatts ( ) 1000 gigawatts
A
1 gigawatt
21
Q
Electricity from a AAA battery costs the consumer about: ( ) 1 cent per kilowatt- hour ( ) 10 cent per kilowatt-hour ( ) $1 per kilowatt- hour ( ) $1000 per kilowatt- hour
A
$1000 per kilowatt-hour
22
Q
Electricity from a wall plug costs the consumer about ( ) 1 cent per kilowatt- hour ( ) 10 cent per kilowatt-hour ( ) $1 per kilowatt- hour ( ) $1000 per kilowatt- hour
A
10 cents per kilowatt hour
23
Q
The energy per gallon of liquid hydrogen, compared to gasoline, is about ( ) 3x less ( ) about the same ( ) 3x more ( ) 12x more
A
3x less
24
Q
Most of the hydrogen we use in the US comes from
( ) pockets of hydrogen gas found underground
( ) hydrogen gas extracted from the atmosphere
( ) hydrogen produced in nuclear reactors
( ) it is manufactured from fossil fuels and/or water
A
it is manufactured from fossil fuels and/or water
25
```
You have a 10 tungsten bulbs, and each uses 100 watts. You leave them all on for an hour. The energy used is
( ) 10 kilowatt-hours
( ) 1 kilowatt- hour
( ) 10 killowatts
( ) 1000 watts
```
1 kilowatt-hour
26
The kinetic energy of a bullet, per gram, is (within a factor of 2)
( ) about the same as the energy released from one gram of TNT
( ) about the same as the kinetic energy in a typical one gram meteor
( ) about the same as the energy released by one gram of chocolate chip cookies
( ) none of the above
none of the above
27
```
If you double the energy content of a kilogram of gas, the temperature of the gas (measured on the absolute K scale):
( ) is unchanged
( ) increases by the square-root of 2
( ) doubles
( ) is multiplied by 4
```
doubles
28
```
About how fast are molecules in air moving?
( ) 1000 ft/s
( ) the speed of light
( ) 9.8 m/s
( ) 9.8 cm/s
```
1000 ft/s
29
```
Temperature is the measure of
( ) average momentum
( ) average kinetic energy
( ) average velocity
( ) average total energy
```
average kinetic energy
30
```
In a bucket of water, the instantaneous speed of the molecules is closest to
( ) zero, since they don't move
( ) whatever speed the wood is moving
( ) approximately 1.7 m/s
( ) approximately 1000 ft/s
( ) approximately 186,000 miles per sec
```
approximately 1000 ft/s
31
```
A refrigerator operating in a room
( ) warms the room
( ) cools the room
( ) has no effect on the room
( ) removes water vapor from the room
```
warms the room
32
```
A refrigerator with its door open is operating in a room. It
( ) warms the room
( ) cools the room
( ) has no effect on the room
( ) removes water vapor from the room
```
warms the room
33
```
A table has the same temperature as the air above it. That means that the molecules in the air and in the table have
( ) The same average velocity
( ) The same average energy
( ) The same average acceleration
( ) The same average mass
```
The same average energy
34
```
Ice melts at
( ) 0 K
( ) 0 C
( ) 0 F
( ) 100 C
```
0 C
35
```
A gas heater warms a room mostly through
( ) convection
( ) conduction
( ) radiation
( ) depletion
```
Convection
36
The velocity of sound
( ) increases when the temperature increases
( ) decreases when the temperature increases
( ) depends on the pressure of the air
( ) is constant, independent of the temperature
Increases when the temperature increases.
37
If a gasoline engine produces a hotter explosion, then the efficiency of the engine should
( ) be the same
( ) go up
( ) go down
go up
38
A cup full of water made of plastic feels warmer than one made of glass because:
( ) plastic is warmed by water
( ) plastic conducts heat less than glass
( ) plastic conducts heat better than glass
( ) plastic dissolves in water
plastic conducts heat better than glass
39
```
The atom with the fewest number of
protons is
( ) helium
( ) carbon
( ) hydrogen
( ) oxygen
```
Hydrogen
40
```
How many atoms are there if you move across a human hair? About
( ) 25
( ) 125,000
( ) 273,000,000,000
( ) 6 x 10^23
```
125,000
41
```
The speed of sound is approximately
( ) 1 foot per nanosecond
( ) 1 foot per second
( ) 1000 feet per second
( ) 186,000 miles per hour
```
1000 feet per second
42
Put hot glass in cool water. It shatters because
( ) it heats the surface water to boiling
( ) the outer surface of the glass contracts rapidly, but the inner part doesn't
( ) the outer surface of the glass expands rapidly
( ) the rapid conduction of heat triggers strong vibrations
the outer surface of the glass contracts rapidly but the inner part doesnt
43
Sea level is rising from global warming. The main cause is
( ) expanding sea water
( ) melting glaciers
( ) expanding rock under the sea
( ) contracting earth (while the water stays constant)
expanding sea water
44
```
The temperature warms by 2 C. That is
approximately the same as
( ) 1 F
( ) 2 F
( ) 4 F
( ) 1/2 F
```
4 F
45
```
Heat a room using the least energy by
( ) burning natural gas (methane)
( ) using natural gas to run a heat pump
( ) burning coal
( ) burning gasoline
using natural gas to run a heat pump
```
using natural gas to run a heat pump
46
There is almost no hydrogen gas in the atmosphere because
( ) it escapes the earth's gravity
( ) there is very little hydrogen in the oceans or land
( ) hydrogen molecules move slower than oxygen and nitrogen
( ) hydrogen has all sunk to the earth's core
it escapes the earth's gravity
47
```
At Mach 10, if all the energy of a meteorite went into heating it, its temperature would be about
( ) 300 C
( ) 6000 C
( ) 30,000 C
( ) 100,000 C
```
100,000 C
48
The New Orleans levees failed because
( ) thermal expansion broke them
( ) they were made of continuous concrete that could not stand the pressure
( ) they had leaks at the thermal expansion joints
( ) they were weaker at the thermal expansion joints
they were weaker at the thermal expansion joints
They were weaker at the thermal expansion joints
49
```
If temperature rises by 5 C = 9 F, then the rise in sea level will be about
( ) 2 inches
( ) 4 feet
( ) 12 feet
( ) 97 feet
```
4 Feet
50
```
For a typical auto, the fraction of the
gasoline energy wasted as heat is about (careful, this may be a trick question):
( ) 1%
( ) 10%
( ) 20%
( ) 80%
```
80%
51
```
The temperature in the sun
( ) is always hotter than in the shade
( ) is always the same as in the shade
( ) is sometimes cooler than in the shade
( ) is not well defined
```
Is always the same as in the shade
52
```
When material is cooled
( ) it stays the same size
( ) it contracts
( ) it expands
( ) some materials contract and some expand
```
Some materials contract and some expand
53
```
The melting temperature of an object is usually
( ) equal to its freezing point
( ) higher than the freezing point
( ) lower than the freezing point
( ) equal to the boiling point
```
Equal to its freezing point
54
```
Absolute zero is the temperature of
( ) frozen water
( ) the universe
( ) liquid helium
( ) nothing
```
Nothing
55
```
When a liquid boils, the increase in volume (liquid to gas) is typically a factor of
( ) 10
( ) 100
( ) 1000
( ) 1,000,000
```
1000
56
```
If the temperature of a gas in a container goes from 0 C to 300 C, the pressure will
( ) stay the same
( ) double
( ) become 300 times greater
( ) become infinite
```
become 300 times greater
57
```
Firewalking is similar to
( ) water on a saucepan
( ) the space shuttle reentry
( ) automobile air bag
( ) water skiing
```
Water on a saucepan
58
```
For gasoline to explode, it requires
( ) to be mixed with oxygen
( ) to be mixed with nitrogen
( ) to be mixed with carbon dioxide
( ) no mixing needed; just a spark
```
to be mixed with oxygen
59
To be more efficient, the temperature difference (between the ignited hot fuel and the cool part of the engine) should be
( ) as small as possible
( ) as large as possible
( ) it doesn't matter
as large as possible
60
```
Heat flow through empty space (no atoms present)
( ) is impossible
( ) occurs through conduction
( ) occurs through convection
( ) occurs through radiation
```
occurs through radiation
61
```
Entropy (optional topic) measures
( ) heat
( ) temperature
( ) disorder
( ) energy
```
Disorder
62
```
Energy in the Sun is produced primarily by
( ) fossil fuels
( ) neutrinos
( ) fission
( ) fusion
```
Fusion
63
```
The mass of the nucleus is closet to
( ) 99% of that in the entire atom
( ) 1% of that in the atom
( ) 10^-5 of that in the atom
( ) 10^-15 of that in the atom
```
99% of that in the entire atom
64
```
Radioactivity in the Earth leads to
( ) energy for volcanos
( ) helium for toy balloons
( ) heat for geysers
( ) all of the above
```
all of the above
65
```
LD50 refers to a
( ) lethal dose
( ) legal dose
( ) large dose
( ) lowest dose
```
Lethal Dose
66
A major reason that your body is radioactive is that
( ) it is slightly contaminated by debris from nuclear tests
( ) it is made radioactive by medical x-rays
( ) you can eat radioactive carbon in your food
( ) you are hit by neutrinos from the Sun
You can eat radioactive carbon in your food
67
```
The primary cause of death from the Hiroshima bomb was
( ) radiation-induced cancer
( ) the blast from the bomb
( ) fallout from the bomb
( ) smoking induced by fear of the bomb
```
The blast from the bomb
68
Fission fragments are
( ) harmless particles emitted in radioactivity
( ) among the most dangerous kind of radiation
( ) ghost-like particles that pass through the Earth
( ) the source of most energy in the Sun
Among the most dangerous kind of radiation
69
Wine made from fossil fuels is not radioactive because
( ) the radioactivity has decayed away
( ) there is no carbon in such wine
( ) ancient plants never were radioactive
( ) the half-life of the key elements is to long
the radioactivity has decayed away
70
If the half-life of an element is big, that means that
( ) it decays faster than one with a small half-life
( ) it decays slower than one with a small half-life
( ) it belongs to a very heavy element
( ) it emits lots of neutrons when it decays
it decays slower than one with a small half life
71
Muller wears a wristwatch with tritium in the watch hands because
( ) he is not worried about radioactivity
( ) tritium is not radioactive
( ) the levels of radiation that emerge are safe
( ) no radiation emerges from the watch hands
no radiation emerges from the watch hands
72
```
After three half-lives, the fraction of nuclei remaining is
( ) 1/2
( ) 1/3
( ) 1/4
( ) 1/8
```
1/8
73
Most of the elements found on the earth were created
( ) in the first few million years of the Earth's existence
( ) within a star
( ) in the Big Bang
( ) in a supernova
within a star
74
```
The fraction of the U.S. population that dies from cancer is typically
( ) about 1 in 10,000
( ) about 1 in 100
( ) about 1 in 5
( ) Most of us die from cancer
```
About 1 in 5
75
Watch dials containing radium glow because
( ) all radioactivity creates light
( ) batteries supply energy when a button is pushed
( ) the radiation hits a phosphor
( ) They don't glow. Only tritium glows.
The radiation hits a phosphor
76
```
Mark all the items that derive from radioactivity:
( ) helium for children's balloons
( ) volcanic lava
( ) warmth in deep mines
( ) most cancer in the United States
```
- Helium for children's balloons
- volcanic lava
- warmth in deep mines
77
```
After four half-lives, the surviving tritium atoms are removed. Compared to completely new tritium atoms, they are expected to live
( ) 1/8 as long
( ) 1/4 as long
( ) 1/2 has long
( ) exactly as long
```
Exactly as long
78
```
One rem of radiation dose takes how many gammas per square centimeter?
( ) about 1
( ) about 5000
( ) about a million
( ) about 2,000,000,000
```
about 2,000,000,000
79
It takes a larger dose of radiation to cause
( ) radiation poisoning
( ) cancer
( ) they are very close in amount needed
Cancer
80
The "linear hypothesis" is (mark all that are correct)
( ) known to be true
( ) widely used even though it is not proven
( ) known to be false
( ) generally ignored in analysis of radiation deaths
Widely used even though it is not proven
81
```
A Sievert is how many rem?
( ) 1
( ) 0.01
( ) 100
( ) 1000
```
100
82
```
Cancer is lower in Denver because
( ) the radiation is lower
( ) the radiation is higher
( ) there are more gamma rays even though there are fewer betas
( ) we don't know why
```
We DON'T know why
83
```
The number of deaths from the Chernobyl accident is about
( ) less than 1
( ) 4,000
( ) 24,000
( ) over a million
```
24,000
84
```
Radioactivity is used in
( ) flashlights
( ) TV screens
( ) fluorescent lights
( ) smoke detectors
```
Smoke Detectors
85
```
Neutron activation is used
( ) to treat cancer
( ) to search for rare atoms
( ) to provide energy
( ) to create light
```
To search for rare atoms
86
Dirty bombs may be less of a threat than people fear, because
( ) once spread out, the rem level drops below the radiation illness threshold
( ) dirty bombs require plutonium, and that is hard for terrorists to obtain
( ) the radioactivity is too small to induce cancer
( ) the radiation does not actually get out of the bomb case, even when exploded
Once spread out, the rem level drops below the radiation illness threshold
87
```
Radioactivity in the Earth is responsible for
( ) helium we use in balloons
( ) warmth to keep the oceans liquid
( ) creation of the oxygen we breathe
( ) navigation of birds
```
Helium we use in balloons
88
```
Volcanic heat comes from
( ) radioactive explosions
( ) the weight of rock
( ) accumulated sunlight
( ) fusion deep in the earth
```
Radioactive explosions
89
```
The best way to measure the age of an ancient bone is
( ) potassium-argon dating
( ) neutron activation
( ) controlled thermonuclear fusion
( ) radiocarbon dating
```
Radiocarbon dating
90
An RTG (Radioisotope Thermoelectric Generator) is
( ) a type of bomb
( ) used in hospitals for power
( ) carried in pacemakers to supply power
( ) carried in satellites for power
Carried in satellites for power
91
Uranium is found on earth, even though it is radioactive. That's because
( ) it is constantly made by cosmic rays
( ) it has a very long half-life
( ) it is created in fusion in the sun
( ) it is created by fusion in the earth
it has a very long half-life
92
```
Carbon-14, compared to carbon-12,
( ) has more protons
( ) has more neutrons
( ) has more electrons
( ) has a shorter half-life
```
Has more neutrons
93
```
Alexander Litvinenko was assassinated with
( ) plutonium
( ) tritium
( ) radium
( ) polonium
```
Polonium
94
The radiation from cell phones
( ) does not cause cancer
( ) causes cancer, but not enough to worry
( ) causes over 1% of the cancer in those who use them
( ) protects users from cosmic rays
Does not cause cancer
95
```
The threshold for radiation illness is about
( ) 1 rem
( ) 100 rem
( ) 500 rem
( ) 2500 rem
```
100 Rem
96
```
The natural radioactivity (rate of nuclear decays) in a typical human body is closet to
( ) 0.2 per hour
( ) 12 per hour
( ) 12 per minute
( ) 4000 per second
```
4000 per second
97
```
The source of energy in the Sun is
( ) uranium chain reaction
( ) radioactivity of tritium
( ) fusion of hydrogen
( ) radioactivity of potassium-40
```
Fusion of hydrogen
98
```
Which of the following is most toxic per gram?
( ) arsenic
( ) Botox
( ) water
( ) plutonium
```
Botox
99
The radioactivity from your own body
( ) does not cause cancer because it is natural
( ) is responsible for more than half of the cancer in humans
( ) does cause cancer, but at a very low rate
( ) helps reduce natural cancer, just as radiation therapy does
Does cause cancer, but at a very low rate
100
Drinking alcohol is required to be radioactive because
( ) it proves that it is not made of petroleum
( ) it is healthier
( ) it shows that the alcohol was "aged"
( ) it is not required; just the opposite, alcohol for consumption must not be radioactive
It proves that it is not made of petroleum
