unit 6 progress check : mcq part a&b
which of the following best describes the total consumption of all fossil fuels in 2040 compared to the consumption of nuclear energy in 2040?
a) consumption of fossil fuels will be approximately 13 times greater than consumption of nuclear energy. -predicted consumption of fossil fuels is approximately 645 quadrillion BTUs in 2040, predicted nuclear consumption is approximately 50 quadrillion BTUs. 248 BTUs from liquid fuels + 125 BTUs from natural gas + 180 BTUs from coal /48 BTUs = 12.86
after the Industrial Revolution, the use of fossil fuels increased significantly. Despite the documented environmental effects of these resources and the availability of renewable resources, the use of nonrenewable sources continues. which of the following statements best explains why there is continued widespread use of nonrenewable fossil fuels in energy production in the United States?
a) established technology and transportation infrastructure for fossil fuels allows these resources to be converted into energy to meet consumer demand.
which of the following describes a step in the generation of electricity using fossil fuels that can most directly lead to an environmental problem?
a) fossil fuel is burned to boil water.
which of the following is a disadvantage of using hydrogen fuel cells?
a) hydrogen gas is not readily available on Earth.
natural gas, a nonrenewable fossil fuel, is often seen as an alternative fuel in the worldwide transition to a renewable energy future. which of the following statements best explains why natural gas is often used as a fuel when countries are transitioning from nonrenewable to renewable energy sources?
a) natural gas burns more efficiently and cleanly than other sources of carbon-based fossil fuels, thus contributing to a reduction in atmospheric carbon dioxide.
Refrigerator A uses 500 watts per hour when the motor is operating. The motor needs to run an average of 12 hours per day, every day, to stay at a constant, cold temperature. This model of refrigerator lasts an average of 20 years before it needs to be replaced and costs $1,000. Each kWh of electricity costs $0.12. the homeowner is considering purchasing a new model of refrigerator, Refrigerator B. This model uses 50 percent less energy per year. Which of the following would be the estimated cost savings for the homeowner in a year if she replaces Refrigerator A with Refrigerator B?
b) $131.40 -annual energy usage for refrigerator A (determined by previous question) x cost per kWh / 2 (2,190 kWH ($0.12) /2 = $131.40
solar energy systems have been increasing the percentage of energy they contributed to the global energy supply. One of the fastest growing types of solar energy systems uses photovoltaic (PV) cells. The graph below shows the solar power generated in one day in a country in the Northern Hemisphere in the month of July.
b) 12 PM - 2 PM
which of the following is the approximate projected rate of change in renewable energy consumption from 2010-2040 ? -unit change formula/work
b) 2.33 quadrillion BTUs per year -the change in projected renewable consumption (about 70 quadrillion) was divided by the change in time (30 years). 130 BTUs - 60 BTUs / 30 years = 2.33 quadrillion BTUs per year
a state is looking to reduce the cost of transportation, which uses 7.10×10147.10×1014 BTUs per year. Currently the cost of 106106 BTUs is $20.00. How much will the state save in one year if they implement regulations requiring all transportation methods to be 20% more efficient?
b) 2.84 x 10⁹ dollars current usage: (7.10 x 10¹⁴ BTUs x 0.20) = 1.42 x 10¹⁴ BTUs current cost is $20 per one mil BTU: 1.42 x 10¹⁴ /1 x 10⁶ = 1.42 x 10⁸ x $20 = $2.84 x 10⁹ or 2.84 billion
which of the following correctly depicts the nuclear chain reaction that occurs in a nuclear power plant?
b) all neutrons -one neutron hits another, resulting in several more neutrons, hitting another neutron, making more neutrons
which of the following is required to convert geothermal energy into electricity?
b) groundwater
which of the following best explains energy transformation in hydrogen fuel cells?
b) hydrogen reacts with oxygen to produce water, which releases energy.
which of the following best identifies a benefit of using renewable energy sources rather than nonrenewable energy sources?
b) renewable energy sources are replenishable and are virtually inexhaustible by human consumption, whereas nonrenewable sources do not form in a short period of time.
which of the following statements correctly describes a difference between biomass-fired power plants and traditional fossil-fuel-burning power plants, such as coal-fired plants?
b) the operational costs of biomass plants are very high when compared with traditional fossil fuel plants.
which of the following geologic profiles would most likely be found at the circled region in the figure? -northern hemisphere, coal deposits
b) top to bottom: peat (leaves), peat (leaves), sedimentary rock, igneous rock
which of the following is an example of the process of cogeneration?
b) using wastewater from electricity production for heating homes cogeneration: generate electricity and usual heat at the same time
wind energy is increasingly relied upon to help meet global energy needs. wind energy can be used to generate electricity using wind turbines. which of the following best describes electricity generation using wind turbines?
b) wind turbines can be constructed on either vertical or horizontal axes.
which of the following best describes why people in less developed countries use wood as a primary energy source?
d) wood, in the form of firewood and charcoal, is often readily available.
Refrigerator A uses 500 watts per hour when the motor is operating. The motor needs to run an average of 12 hours per day, every day, to stay at a constant, cold temperature. This model of refrigerator lasts an average of 20 years before it needs to be replaced and costs $1,000. Each kWh of electricity costs $0.12. how many kilowatt hours (kWh) per year does refrigerator A use?
c) 2, 190 kWh -usage converted W to kW. value multiplied by the number of hours the motor runs per day and then by the number of days in a row. 500 W (1 kW/1,000 W) (12 hours/1 day) (365 days/1 year) = 2,190 kWh
based on the data above, approximately how much greater is the average cost of electricity produced in the United States from offshore wind than from hydroelectric power?
c) 2.3 times greater -average cost of energy produced form offshore from wind farms is $197/MWh. average cost of energy produced from hydroelectric power is $84/MWh. $197 / $84 = 2.3 times greater
which of the following identifies the air pollutants most commonly released during the burning of biomass?
c) Carbon dioxide ( CO2 ), particulate matter ( PM ), and carbon monoxide ( CO )
wind energy is increasingly relied upon to help meet global energy needs. wind energy can be used to generate electricity using wind turbines. which of the following correctly identifies the sequence of energy conversions that occur in a wind turbine?
c) Kinetic energy →→ mechanical energy →→ electrical energy
wind energy is increasingly relied upon to help meet global energy needs. wind energy can be used to generate electricity using wind turbines. which of the following are often used for energy storage of wind power?
c) batteries
which of the following is an environmental benefit associated with substituting ethanol for gasoline?
c) burning ethanol produces fewer air pollutants than burning gasoline alone.
at which of the following locations in the nuclear power plant would an accident most likely result in the release of fission products?
c) containment building -reactor vessel holds the uranium fuel that is undergoing fission reactions that results in heat production (reactor is where melt downs occur)
which of the following best describes a potential advantage of using geothermal energy instead of solar farms for power generation?
c) geothermal energy can be harnessed without destroying large tracts of habitat, whereas solar farms require large amounts of space.
geothermal energy is used to run large and complex power stations as well as small and relatively simple pumping systems. which of the following most accurately explains how geothermal energy is produced and utilized in these applications?
c) geothermal energy uses the natural insulating power of Earth to create temperature differentials that are used to heat buildings in the winter and cool them in the summer.
which of the following statements best describes a difference between nonrenewable and renewable energy sources?
c) renewable energy sources can be replaced naturally at current consumption rates, whereas nonrenewable energy sources cannot be replaced easily.
if a country possesses large oil and gas reserves within its borders, which of the labeled rock types must be present in the underlying geology of the country?
c) sedimentary rock
a diagram of a pressurized water nuclear reactor is shown below. in the diagram above, which letter correctly identifies the step where kinetic energy is converted to mechanical energy?
c) turbine, generator -kinetic energy of the water molecules causes the turbines to spin, converting kinetic energy to mechanical energy
solar energy systems have been increasing the percentage of energy they contributed to the global energy supply. One of the fastest growing types of solar energy systems uses photovoltaic (PV) cells. The graph below shows the solar power generated in one day in a country in the Northern Hemisphere in the month of July. which of the following best describes how a homeowner using an off-the-grid PVPV solar system, in the same country as seen in the graph above, can power a home between 9:00 PM and 6:00 AM?
c) using excess energy from a sunny day stored in batteries for power
which of the following best describes an environmental problem that is often linked to the process of fracking?
c) wastewater from fracking operations is injected into porous rock formations, which can induce seismic activity.
which of the following best describes a potential negative environmental effect of fossil fuel extraction?
d) air pollutants, such as methane and particulate matter, are emitted into the atmosphere.
a hydrogen fuel cell-powered car driving on a highway is different from gasoline-powered cars because hydrogen fuel cell-powered cars only emit
d) water vapor and heat