Calculating the Cost of Climbing Stairs: $4.75?

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The discussion revolves around calculating the cost of energy used while climbing stairs. The original poster calculated using 165 watts over 10 seconds, leading to a total of $4.75 for an hour of climbing. However, a participant clarified that watts measure power, not energy, and suggested the correct conversion would yield only 1.2 cents for an hour of similar activity. The confusion stemmed from not converting joules to kilowatt-hours properly. Ultimately, the correct cost for climbing stairs is significantly lower than initially calculated.
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I used 165 watts to climb a set of stairs 3m high for 10s(550n*3m/10s). My electric company supplies 1kw for 1hr for 8 cents. If I climbed those stairs for 1 hour how much money would it be worth? I multiplied 165 by 360 divided by 1000 to get 59.4kw's. If I multiply 59.4 by .08 I get $4.75. Did I forget something?
 
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Since the problem does not specify the energy consumed for getting down a ladder (it can't be equal to the one for climbing)...I'd say that my answer is 13$ and 20ç.

Daniel.
 
I don't understand what you mean when you say "I used 165 watts to climb a set of stairs 3m high for 10s". A "watt" is a measure of power: energy per second. You can't 'use' a watt in the same way you would 'use' a Joule (or, for that matter, a "watt-second" or "kilowatt-hour").

If you mean that you averaged 165 watts of power output for all the 10 seconds, then you produced 1650 "watt-seconds"= 0.00041666.. kilowat-hours. Working at that for a full hour, 360 of the 10 second units, you would have produced 0.15 kilowatt-hour, worth, at the rate you give, 1.2 cents.
 
Thank's HallsofIvy! I should have converted joules to kwh's.
 
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