Maybe we should put #3 into scientific notation. How would you write that?
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Question 5
5.
How would you put 0.000071 in scientific notation?
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Question 6
6.
Solve this using scientific notation. 5.2x1014 X 7.0x1012
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Question 7
7.
Solve this using scientific notation. 4.0x1025 X 2.0x1012
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Question 8
8.
Imagine that you had unlimited time and you needed to get from Houston, TX to Wichita Falls, TX. The distance is roughly 600 km (375 miles). For each mode of transportation, calculate how many megajoules of energy you would use to make the trip.
Airplane - 3.1 MJ per passenger/km
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Question 9
9.
Imagine that you had unlimited time and you needed to get from Houston, TX to Wichita Falls, TX. The distance is roughly 600 km (375 miles). For each mode of transportation, calculate how many megajoules of energy you would use to make the trip.
Car (driver only) - 2.6 MJ per passenger/km
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Question 10
10.
Imagine that you had unlimited time and you needed to get from Houston, TX to Wichita Falls, TX. The distance is roughly 600 km (375 miles). For each mode of transportation, calculate how many megajoules of energy you would use to make the trip.
Train - 1.3 MJ per passenger/km
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Question 11
11.
Imagine that you had unlimited time and you needed to get from Houston, TX to Wichita Falls, TX. The distance is roughly 600 km (375 miles). For each mode of transportation, calculate how many megajoules of energy you would use to make the trip.
Bus - 1.5 MJ per passenger/km
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Question 12
12.
If a gallon of gasoline contains 120 MJ, how many gallons of gasoline does it take to make the trip by car?
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Question 13
13.
If you could carpool with three other people who needed to make the same trip, what would the energy expenditure be for each person?
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Question 14
14.
Included the energy calculation of the car with 4 people (including the driver) which form of transportation would be most efficient?
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Question 15
15.
An Energy Star air conditioner unit costs $300 while a standard unit costs $200. The two units have the same cooling capacity. The Energy Start unit costs 10 cents per hour less to run. If you buy the Energy Star unit and run it for 12 hours per day for 6 months (say 30 days/month) of the year, how long does it take to recover the $100 extra cost?
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Question 16
16.
You are about to invest in a 75-inch flat-screen TV. These TVs come in both Energy Star and non-Energy Star models. The cost of electricity is $0.11 per kilowatt-hour, and you expect to watch TV an average of 4 hours per day. (WAY TOO MUCH!!)
The non-Energy Star model uses 0.5 kW (half a kilowatt). How much will it cost you per year for electricity to run this model?
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Question 17
17.
You are about to invest in a 75-inch flat-screen TV. These TVs come in both Energy Star and non-Energy Star models. The cost of electricity is $0.11 per kilowatt-hour, and you expect to watch TV an average of 4 hours per day. (WAY TOO MUCH!!)
If the Energy Star model uses only 40 percent of the amount of electricity used by the non-Energy Star model, how much money would you save on your electric bill over 5 years by buying the more efficient model?
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Question 18
18.
A power plant has a capacity of 500 MW. This is the maximum electrical output of the plant when it is operating. The plant has a 0.9 capacity factor, a measure of the actual time a plant operates. The capacity factor is a fraction of the total time that the plant could operate.
Accorrding to the U.S. Department of Energy, a typical home in the U.S. uses approximately 900 kWh of electricity per month.