Calculating the Cost of Climbing Stairs: $4.75?

  • Thread starter Thread starter extreme
  • Start date Start date
AI Thread Summary
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.
extreme
Messages
7
Reaction score
0
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?
 
Physics news on Phys.org
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.
 
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Correct statement about a reservoir with an outlet pipe'
The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
Back
Top