1.

Consider the following statement.

I ran a distance of of 3.1 miles in 24.3 minutes. That means I ran an average of 0.1275720165 miles per minute!

Select the choice that best describes a problem with this statement.A)It is not physically possible for a person to run that fast; the statement cannot be true. B)The math is incorrect; it should be 7.84 miles per minute. C)There is nothing wrong with this statement. D)The figure suggests a precision that isn't accurate; it should be written as 0.13 miles per minute. E)Miles per minute cannot be calculated because 24.3 minutes isn't a real measurement. 2.

According to research lead by Martin Arvidsson of Stockhom University, humans can detect variations in surface height as small as 13 nanometers: (1.3108meters1.3108meters).

An article in National Geographic reporting on this research stated that this is about'the width of a human hair.'

The width of human hair varies, but is typically about5105meters5105meters. Compare the width of a human hair with the 13 nanometers reported as the limit of the sensitivity of human touch.

A)The width of a human hair is larger by a factor of about 40 B)These quantities are the same order of magnitude. C)The width of human hair is smaller by a factor of about 300 D)The width of a human hair is larger by a factor of about 4000. E)The width of a human hair is smaller by a factor of about 3000. 3. At the Glen Canyon Powerplant water from Lake Powell drops 150 meters and is discharged back into the Colorado River. The maximum flow rate through the plant is 950 cubic meters per second. Estimate the maximum amount of power that could be generated (1 kilogram of water falling through 1 meter releases 10 Joules of energy).A)About 200 MW B)About 3500 MW C)About 1400 MW D)About 15 MW E)About 63000 MW 4.

An electric water heater is set to125F125F. The water heater is in a basement which is kept at65F65F. The water heater is insulated with anRR-value of10ft2FhrBtu10ft2FhrBtuand has a total surface area of 36ft236ft2. Estimate the monthly cost of the heat energy that is lost through the walls of the water heater (1 kilowatt-hour = 3400 Btu and the cost of 1 kilowatt-hour is $0.12).

A)About $60 per month B)About $10 per month C)Less than $1 per month D)About $25 per month E)About $5 per month 5. Solar thermal plants use molten salt heated to570C570Cto store thermal energy. Use Stephan's Law to estimate the power output of a sphere of molten salt at this temperature, having a radius of half a meter (recall the temperature units used in Stephan's Law).A)About 20 kilowatts. B)About 180 kilowatts. C)About 600 kilowatts. D)About 1200 watts. E)About 90 kilowatts. 6.

Mercury has a solar constant of approximately9100Wm29100Wm2and an albedo of 0.07. Calculate the temperature of the surface of Mercury predicted by the 'naked planet model' (in Kelvins).

A)About 700 K B)About 800 K C)About 255 K D)About 520 K E)About 440 K 7.

This question refers to the post"Pilot Lights are Evil", on Tom Murphy's Do the Math blog. Read that post carefully before attempting the following question Use the unit conversions described in the post to convert a natural gas consumption rate of 5 cubic feet per hour to kilowatt-hours per month.

A)About 110,000 kilowatt-hours per month B)About 3600 kilowatt-hours per month C)About 1500 kilowatt-hours per month D)About 1000 kilowatt-hours per month E)About 15,000 kilowatt-hours per month 8.

This question refers to the post"Pilot Lights are Evil", on Tom Murphy's Do the Math blog. Read that post carefully before attempting the following question.

In the summer of 2007, Tom Murphy shut off the pilot light for the furnace in his condo. After making this change what percentage of his monthly summertime natural gas use was going to pilot lights?

A)About 25% B)About 15% C)About 35% D)About 70% E)About 45% 9.

This question refers to the post"Pilot Lighs are Evil", on Tom Murphy's Do the Math blog. Read that post carefully before attempting the following question.

Which of the following is the main thing Tom Murphy is advocating for in his post?

A)Shut off the pilot lights on your natural gas appliances. B)Replace your natural gas water heater with an electric water heater. C)Convert all of your energy consumption to the units of kilowatt-hours. D)Take short showers, every other day. E)When replacing a natural gas appliance, choose a replacement that does not use a pilot light. 10.

This question refers to the post"Pilot Lighs are Evil", on Tom Murphy's Do the Math blog. Read that post carefully before attempting the following question.

During the winter months my natural gas furnace runs an average of 1.5 hours per day. If the 1/2 cubic ft dial on my natural gas meter takes 30 seconds to go once around when the furnace is running, how much energy is my furnace consuming each day, in kilowatt-hours?

A)About 180 kilowatt hours per day B)About 2700 kilowatt hours per day C)About .20 kilowatt hours per day D)About 20 kilowatt hours per day E)About 26 kilowatt-hours per day 11.

This question refers to the post"Pilot Lighs are Evil", on Tom Murphy's Do the Math blog. Read that post carefully before attempting the following question.

Which of the following ideas is closest to the main thesis of this post?

A)Energy consumption should always be expressed in units of kilowatt-hours to facilitate comparisons. B)Pilot lights are evil. C)By making small changes in how we use energy at home, we can reduce human caused emissions of carbon dioxide to a safe level. D)Most of the energy wasted in a typical household is due to pilot lights. E)Awareness of our personal resource consumption can lead to a significant impact via changes in behavior and consumer choice. 12.

This question refers to the post"Pilot Lighs are Evil", on Tom Murphy's Do the Math blog. Read that post carefully before attempting the following question.

During the summer months Tom's hot water needs require 5 MJ of energy per day; the hot water heater's pilot light consumes 11 MJ of energy per day. Express the waste heat per day in Btu's per hour.

A)About 240 Btu/hr B)About 150 Btu/hr C)About 1200 Btu/hr D)About 2600 Btu/hr E)About 5700 Btu/hr