Review Flashcards
Which measurement unit could be used to express power? The symbol BTU stands for British Thermal Unit, and the symbol h stands for hour.
A) BTU
B) BTU.h
C) BTU.h^2
D) BTU/h
D) BTU/h
How much electrical energy will be used by a TV set with power rating of 200 W if it operates for 10 hours?
A) 2000 W
B) 200 W.h
C) 20 kW.h
D) 2 kW.h
D) 2 kW.h
What is the power rating of a typical nuclear reactor?
A) 10 kW
B) 100 W
C) 1000 MW
D) 10000 W
C) 1,000 MW
Which value indicates the greatest amount of power?
A) 1.0 kW
B) 0.1 MW
C) 1000 MW
D) 10000 W
C) 1000 MW
In 2008, the world relied on fossil fuels for ____ and on oil for ___, respectively, for its energy consumption.
A) 50%, 20%
B) 20%, 37%
C) 37%, 85%
D) 85%, 37%
D) 85%, 37%
Which country is the top petroleum importer into the U.S.?
A) Russia
B) Saudi Arabia
C) Iraq
D) Canada
D) Canada
At present, the U.S. energy consumption is approximately
A) 1 Qbtu
B) 10 Qbtu
C) 100 Qbtu
D) 1000 Qbtu
C) 100 Qbtu
Which sector in the U.S. economy is the greatest consumer of petroleum?
A) Residential and Commercial Buildings
B) Generation of Electricity
C) Industry
D) Transportation
D) Transportation
What fraction of the coal supply of the USA is used for the generation of electricity?
A) 91%
B) 9%
C) 19%
D) 29%
A) 91%
Which of the renewable resources has the most available power?
A) Wind
B) Geothermal
C) Solar
D) Hydro
C) Solar
What type of energy transformation takes place in a hydro-electric power station?
A) gravitational potential energy -> kinetic energy -> electrical energy
B) kinetic energy -> gravitational potential energy -> thermal energy
C) electrical energy -> thermal energy -> electrical energy
D) nuclear energy -> electrical energy -> kinetic energy
A) gravitational potential energy -> kinetic energy -> electrical energy
What is a typical rotational speed for a Flywheel Energy Storage device?
A) 20 rpm
B) 200 rpm
C) 2000 rpm
D) 20000 rpm
D) 20000 rpm
Which method of heat transfer is predominant in solid materials?
A) conduction
B) radiation
C) convection
D) condensation
A) conduction
The changing of which parameter will have the greatest effect on the wind power?
A) density of air
B) blade diameter
C) wind speed
D) blade radius
C) wind speed
What is the maximum possible efficiency of a heat engine operation on a temperature of 100 K and temperature of the hot reservoir T_max=500 K?
A) 100%
B) 50%
C) 20%
D) 33%
C) 20%
Which quantity represents the rate of flow of electric charge?
A) Voltage
B) Curent
C) Power
D) Resistance
B) Current
What amount of current flows through an electrical heater connected to potential difference (cottage) of 100 V and converting electrical energy into heat at a rate of 5 kW?
A) 50 A
B) 5 A
C) 0.05 A
D0 500 A
A) 50 A
If you double the length of a conducting wire, while keeping all other parameters the same, by what numerical factor dos the wire resistance change?
A) 2 (it doubles)
B) 4 (it quadruples)
C) 1/4 (it decreases to a quarter of its previous value)
D) 1/2 (it is cut in half)
A) 2 (it doubles)
If you connect two batteries, each with voltage 12 V and charge 200 A.h in series, then what are the total voltage and the total charge of the combination?
A) 12V, 200A.h
B) 24V, 400A.h
C) 24V, 200A.h
D) 12V, 400A.h
C) 24V, 200A.h
Which device is used to increase/decrease the voltage in AC electrical distribution systems?
A) Generator
B) Motor
C) Insulator
D) Transformer
D) Transformer
What is the typical efficiency of a coal-burning steam-driven power plant?
A) 55%
B) 15%
C) 35%
D) 95%
C) 35%
What is the primary fuel used in nuclear power plants?
A) Uranium-235
B) Uranium-238
C) Plutonium-239
D) Mercury-200
A) Uranium-235
What is the typical efficiency of a modern large 3-blade wind turbine?
A) 10%
B) 20%
C) 40%
D) 80%
B) 20%
Which type of renewable energy power plant produces the most expensive electrical energy?
A) Wind
B) Solar Photovoltaic
C) Solar Thermal
D) Hydroelectric
B) Solar Photovoltaic
