PSC 1515 Final Exam Review
The isotope Cesium-137, which has a half-life of 30 years, is a product of nuclear power plants. How long will it take for this isotope to decay to about one-sixteenth its original amount?
120 years
If you exert 100 J in 50 s, your power output is
2 W.
The gap between two brain cells is 2.0x 10^-3 nm. How many meters is this?
2.0x 10^-12 m
What percentage of Earth's water is freshwater?
3%
How many joules of energy are in 1 kWh?
3.6MJ
The isotope lithium-7 has a mass of 7.0160 atomic mass units, and the isotope lithium-6 has a mass of 6.0151 atomic mass units. Given the information that 92.58 percent of all lithium atoms found in nature are lithium-7 and 7.42 percent are lithium-6, calculate the atomic mass of lithium, Li (atomic number 3).
6.942 amu
If a neutral element has the following chemical symbol, how many electrons does it have? ^235 92U
92
Water precipitated over land completes its cycle as it A) percolates into the ground. B) evaporates from the surface to the atmosphere. C) enters streams and lakes and makes its way to the oceans. D) all of the above
D) all of the above
Which has zero acceleration? An object A) in mechanical equilibrium. B) at rest. C) moving at constant velocity. D) all of the above E) none of the above
D) all of the above
Temperature differences between daytime and nighttime on Earth are relatively small due to
Earth's relatively high daily spin rate and shortness of nighttime.
The nation that currently has the most progressive renewable energy policies and also produces the greatest amount of electricity from PV solar is
Germany.
Which one of the following is true of hydrogen fuel cell technology?
It has been used widely in NASA's spaceflight programs
_________ has more natural gas reserves than any other country.
Russia
Elements above uranium in the periodic table do not exist in any appreciable amounts in nature because they have short half-lives. Yet there are several elements below uranium in atomic number with equally short half-lives that do exist in appreciable amounts in nature. How can you account for this?
These isotopes result from the radioactive decay in uranium.
Which of the following statements best describes a critical mass?
a critical mass is the minimum amount of material that will undergo nuclear detonation
Cold water will warm to room temperature faster in a
black pot.
Coal is composed of
buried plant material that has partially decayed.
Energy conservation in the United States _______.
can be improved as individuals make conscious choices to reduce personal consumption
A major advantage of hydrogen-generated electricity over other new renewable energy sources is that it ______.
can be produced where and when electricity is needed rather than being intermittent
Although photovoltaic electricity as a power source is cleaner than burning fossil fuels, the problem with this electricity is that it
cannot be stored easily in large quantities for use when and where it is needed.
Which of the following properties most clearly reflects the internal arrangement of atoms in a crystalline material?
cleavage
The primary energy source that is most used in the United States for production of electricity is _______.
coal
The world's most abundant fossil fuel is
coal.
The primary motivation to develop the new renewable energy sources comes from _________.
concerns over diminishing fossil fuel supplies and negative environmental impacts of fossil fuel use
Oil shale deposits
contain organic kerogen which can be produced into petroleum.
If the radius of Earth somehow decreased with no change in mass, your weight would (Hint: use the inverse square law)
decrease
The reason we don't have eclipses monthly is because of the
different orbital planes for Earth and the Moon.
When assessing energy resources, it is helpful to use a measure called EROI, which is
energy returned divided by energy invested.
The change in entropy of a closed reversible system
equals zero.
Earth's magnetic field is attributed to the
flow of molten fluid in Earth's outer core.
Which of the following energy sources is considered nonrenewable?
fossil fuel energy
Wind turbines are generally more productive if they are _____.
higher, to minimize turbulence and maximize wind speed
The current practice of geothermal power generation may not always provide a practical renewable energy source because _____.
in some cases, the heated groundwater is used much faster than it is recharged
In an aquatic ecosystem experiencing eutrophication, levels of dissolved macronutrients _______ and dissolved oxygen levels _________.
increase; decrease
As a system becomes more distorted, entropy
increases.
Instead of only generating electricity, rising energy demands may also be met by ______.
increasing the efficiency of energy consumption
First law of thermodynamics states that the internal energy of a system tends to increase if the energy is added as heat Q and tends to decrease if energy is lost as work W done by the system. If work is done on the system, what happens to the internal energy of the system is no heat is transferred?
internal energy increases since the 1st law depends on the negative work done by the system
Carbon sequestration ______.
involves converting carbon dioxide gas to a liquid form for storage in the ocean or underground
The Keystone XL Pipeline _________.
is a hotly debated pipeline that would carry petroleum from Canada to the southern United States
Ice has a lower density than water because ice
is made of open-structured, hexagonal crystals.
The oil spill resulting from the 2010 Deepwater Horizon disaster ______.
is the largest accidental spill in world history, causing damage to marine and coastal ecosystems
Why is groundwater in an aquifer a nonrenewable resource?
it can take thousands of years for rainwater to percolate downwards to recharge the aquifer
How does the ocean change with increasing depth?
it gets darker and colder, pressure increases and it contains fewer organisms
Solar represents a minuscule portion of U.S. energy production because of ________.
lack of investment
An object that has potential energy may have this energy because of its
location.
Density is the ratio of
mass to volume.
Natural gas is primarily composed of ______.
methane
A polymorph can be defined as
minerals that have the same chemical formula, but different crystal structures.
The Earth rotates about its axis once per 24 hours, while the Moon rotates about its axis once per
month.
If uranium were to split into three segments of equal size instead of two, would more energy or less energy be released?
more energy would be released because of less mass per nucleon
One of the problems with finding new fossil fuel deposits in developing countries is that _______.
multinational companies often move in to harvest the new deposit, and very little money or resource remains in the country
Renewable energy includes all of the following EXCEPT ________.
natural gas
The most cleanly burning fossil fuel available, producing the least pollutants, is _______.
natural gas
Mutualistic relationships between bacteria and certain root nodules play an important role in the global cycling of _______.
nitrogen
A major obstacle to the establishment of wind farms near populated and scenic areas is _______.
not-in-my-backyard (NIMBY) syndrome
A potential energy source from oceans is
ocean thermal energy.
The three kinds of plate convergence are
oceanic-oceanic, continental-oceanic, and continental-continental.
Natural gas is _____.
often associated with coal and petroleum deposits
In the United States, _____ is the leading source of energy.
oil
The two most common igneous rocks are basalt and granite. Basalt is commonly found _______ and granite is found ______.
on both the ocean floor and continental land; only on the continents
If a body is fully or partially submerged in a fluid, a buoyant force directed upward depends
on the mass of the replaced fluid.
If you push for an hour against a stationary wall, no work is done
on the wall.
Every winter morning when the sun is shining bright, a man living in Montana pulls back the drapes on a large, south-facing window. In this way, he helps heat his home using
passive solar heating.
Alaskans benefit from the trans-Alaska pipeline because Alaska's state constitution requires approximately 25% of state revenues associated with the oil industry to be placed into a monetary fund called the Permanent Fund, which ______.
pays yearly dividends to all Alaska residents
U.S. oil production _______.
peaked in 1970
Most of Earth's seismic activity, volcanism, and mountain formation occur along
plate boundaries.
Compared to the use of fossil fuels for generating electricity, wind energy ______.
produces no exhaust pollutants and contributes little to global climate change
The energy bill passed by the U.S. Congress in 2007
raised the CAFE standard to 35 mph for vehicles by the year 2020.
The layered appearance of foliated metamorphic rocks is due to the
realignment of minerals so that they are perpendicular to compressive forces.
Crude oil is _____.
refined to separate the chemicals used for gasoline, lubricants, plastics, and other products
One difficulty with the process of using hydrogen as a power source is that it
requires a substantial energy investment to begin the process.
The fact that one side of the Moon always faces the Earth is evidence that while revolving about the Earth, it
rotates about its axis.
Consider a huge rotating cloud of particles in space that gravitates together to form an increasingly dense ball. As the cloud shrinks in size, it
rotates faster.
What event will eventually move an average star off the main sequence of the H-R diagram?
running out of hydrogen, causing gravitational influx, resulting in core temperatures high enough to begin fusing helium
The salinity of seawater remains constant because
salts are removed from seawater about as fast as they are deposited.
Scientists search for fossil fuels in many ways. Sending a sound wave into the ground (by exploding dynamite, thumping the ground with a large weight, or using an electric vibrating machine) and measuring its return to the surface at receiving stations is called _____ surveying.
seismic
The basic building block of all silicate minerals is the
silicate tetrahedron.
Which requires the most amount of work on the brakes of a car?
slowing down from 100km/h to 70km/h
A major advantage of solar power is that _______.
solar systems provide local, decentralized control over power
"New renewables" are _____.
solar, wind, geothermal
The Organization of Petroleum Exporting Countries (OPEC) _______.
strives to ensure that developing countries get their fair share of fossil fuels
The largest problem with adopting the new technology of renewable resources is ______.
that the startup costs may be high
Wind will not be a major U.S. energy resource in ______.
the Southeast
Which of the following statements best describes the role of neutrons in the nucleus?
the neutrons stabilize the nucleus by forming bonds with other neutrons
Whether a hydrogen-based energy system is environmentally cleaner than a fossil fuel system depends on ________.
the source of energy used to produce the hydrogen
A major disadvantage of solar power is _____.
the uneven distribution of sunshine around the world
Many developed nations have their economies closely tied to important fossil fuels. One important consideration for those nations is that _______.
their economy can be disrupted by the events and decisions made in fuel exporting nations
A star's size stabilizes when
thermal pressure and gravitational attraction balance each other.
Humans shape Earth's surface
to a large degree.
If you do work on an object in half the time, your power output is
twice the usual power output.
Passive solar technologies ______.
use the energy of sunlight without relying on electrical or mechanical devices
Secondary extraction of petroleum ______.
uses solvents, water, or steam
Energy can be conserved by ________.
using cogeneration in power plants, fuel efficient transportation, and reengineered lightbulbs and appliances
Which of the following methods is considered a type of passive solar energy collection?
using heat-absorbing construction materials
As an object free falls, its
velocity increases.
The balance of gravitational and buoyant forces acting on the crust determines its
vertical position.
The chemical product of burning hydrogen fuel cells as an energy source is ______.
water
A rock's permeability can be described by its
water-transmitting capability.
The difference between lightwaves approaching and lightwaves receding is
when approaching, ligtwaves have higher frequency; when receding, their frequency is lower.
One benefit of offshore wind farms is that ________.
wind speeds are higher and turbulence is lower over water than over land