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Homework Help: Watt is the unit of power

  1. Feb 13, 2007 #1
    I had question in practice book, i answered all the math problem, but i couldn't figure out the explantation part of the question

    a) describe the relationship between the time to complete 2000 meter and the average wattage output in rowing machine.

    b) describe the relationship between stroke rate, average wattage output per stroke and the final time.

    also if i have the daily killowatt hour and the total killowatt hour, can i find the financil value of the power generated by (total killowatt hour times the fee of one killowatt hour)
    Last edited: Feb 13, 2007
  2. jcsd
  3. Feb 14, 2007 #2


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    a) The rower does work in order to cover that distance.

    b) The total work done is achieved by doing a little bit of work during each of the strokes.

  4. Feb 14, 2007 #3
    i meant by financial is money that i have to pay when i generate such killowatt hour
  5. Feb 14, 2007 #4


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    Hmmm. A watt is a nt-m/sec, I think. The force required is the drag to move along, and the time allows one to find m/s. That should explain it, right?
  6. Feb 15, 2007 #5


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    kilowatt hour is another unit of energy since power is energy per unit time. If one multiplies power by another time unit you are back to an energy unit. So kilowatt hour is an indication of the amount of (usually electrical) energy consumed in performing some task (running some appliances). So yes, if you know the amount of kilowatt hour units that were used you just need to multiply it by the rate (dollars etc. per kilowatt hour) to get the amount you will have to pay for the energy that was supplied to you.
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