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Energy can be converted to what? ✔Correct Answer-Work, heat, radiation
What are the units of energy? ✔Correct Answer-BTU, Calorie (food calorie), calorie, Joules, kWh,
Therm
What are the units of power? ✔Correct Answer-Watts, kW, J/s, HP, cal/s, Btu/h
One BTU is defined as the amount of energy required to raise the temperature of what? ✔Correct
Answer-Heat one pound of water by one degree Farenheit
One calorie is defined as the amount of energy required to raise the temperature of what?
✔Correct Answer-Heat one gram of water by one degree Celcius
A 100 watt incandescent light bulb is operated for 120 hours, and a 15 watt fluorescent light bulb is
operated for the same period of time. At 10 cents per kWh, what is the cost of savings of the
fluorescent bulb? ✔Correct Answer-1.02
((100/1000)-(15/1000))*(120)*(0.10)
If Peter expends 1,500 calories running a mile in one hour and Samantha burns 1,500 calories riding
a bike in 45 minutes, which of the two spent the greatest amount of energy? ✔Correct Answer-
They are the same.
(Samantha used more power)
If Peter expends 2,000 calories running a mile in one hour and Samantha burns 1,000 calories riding
a bike in 30 minutes, who exerted the greatest amount of energy? ✔Correct Answer-They are the
same
2,000/1=1,000/0.5
Power = ✔Correct Answer-Energy/Time
A refrigerator rated at 494 Watts running 13 hours everyday is replaced by a new refrigerator rated at
221 Watts and runs 8 hours per day. What is the energy saving in kWh for a week? ✔Correct
Answer-32.57
((0.494 * 13)-(0.221*8))*7
True or false: Nuclear fusion is a renewable source of energy ✔Correct Answer-True.
(But nuclear fission is not!)
True or False: a BTU has more energy than a calorie ✔Correct Answer-True
True or False: energy can be converted from one form to another ✔Correct Answer-True
, Geothermal heat can be used to produce electricity ✔Correct Answer-True
What are examples of mechanical energy? ✔Correct Answer-Wind, Tidal energy, coiled spring,
hammer being used to pound nails (kinetic), hammer that is raised in preparation to pound nails
(potential)
Mechanic (potential or kinetic possesses energy by virtue of its motion or by virtue of its position
relative to a reference point
An energy source is nonrenewable if ✔Correct Answer-If the source cannot be regerated in a
reasonable period of time
Examples of renewable energy sources ✔Correct Answer-hydropower, wind, tidal, geothermal
energy from inside the earth, biomass from plans, nuclear fusion
Examples of nonrenewable energy sources ✔Correct Answer-fossil fuels (petroleum, natural gas,
coal), tar sands, nuclear fission
Doubling time= ✔Correct Answer-70/ (% Growth Rate per Year)
What percentage of US energy demand is met by renewable energy sources? ✔Correct Answer-
Less than 10%
What percentage of the US petroleum demand is met by imports? ✔Correct Answer-Around 50%
Which fuel supplies the greatest proportion of primary energy in the US? ✔Correct Answer-
Petroleum
At the present rate of consumption, how long are the US petroleum reserves expected to last?
✔Correct Answer-Less than 10 years
Asia has an estimated reserve of 35,895 mil barrels of oil. The country uses 9,947,399 barrels of oil
per day. At this rate, how many years will the reserves last? ✔Correct Answer-9.89 years
35,895 mil/(9,947,399*365)
Energy use in China is projected to increase at the rate of 3.6% per year. How long will it take for
energy consumption in China to double? ✔Correct Answer-19.44
70/3.6
Energy use in Kunesia is projected to increase at the rate of 3.5% per year. How long will it take for
energy consumption in Kunesia to double? ✔Correct Answer-20 years
70/3.5
True of False: In the next 20 years, it is expected that renewable energy sources will supply more
than half the US energy requirements ✔Correct Answer-False