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Homework Help: Work, Power and Energy

  1. Oct 8, 2015 #1
    1. The problem statement, all variables and given/known data
    "Complete the weekly energy cost and power rating of a TV and clothes dryer by completing the table that follows."

    The table is presented in the thumbnail

    2. Relevant equations
    work = force / distance
    power = work / time

    Y = E * c
    -Y is the yearly running cost
    -E in the EnerGuide energy rating per year
    -c is the cost of electricity per kW/h

    3. The attempt at a solution
    Ive done the first 4 columns of the chart and I know how to solve the last one (By using the p = w * t equation) Problem is....I have no idea how to calculate the "estimate of hours of use per week." Ive been multiplying and dividing the number of hours per week by about anything I can think of but Im not coming up with the correct answer. If anyone can point me in a direction as to what I need to be calculating the help would be greatly appreciated!

    P.S This table was the answer given to us for the example question. The last 2 columns are unfinished on my personal table

    Attached Files:

  2. jcsd
  3. Oct 8, 2015 #2
    Try getting the estimate of hours per week by using the
    E per week and the power calculated in the last row
  4. Oct 8, 2015 #3
    I cant do that because I dont know the power yet. Like I stated The last 2 columns on my chart are empty and i cant calculate power without the time first.
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