1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Fill in the empty columns of a work/power table

  1. Oct 8, 2015 #1
    1. The problem statement, all variables and given/known data
    "Fill in the empty columns of the following table"

    Table is in the thumbnail

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

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

    3. The attempt at a solution
    I have already filled in the first 2 blank rows on the table.
    The E per week is 5.08kWh/week and 17.5kWh/week
    for the running yearly cost Y it is $0.30/week and $1.05/week

    This is where im stuck. I have no idea how to fill out the last 2 columns with the information I currently have. I thought I would need to divide and or multiply a number by 168 (number of hours in a week) but that doesnt seem to do any good. Could someone point me in the direction as to what I need to calculate in order to find the estimated hours of use per week?

    Attached Files:

  2. jcsd
  3. Oct 8, 2015 #2
    It just depends on your choice :)
  4. Oct 8, 2015 #3
    Does that mean that the time is completely up to you to decide? The only reason im confused about this is because this is only a practice question and the actual homework has a table almost identical to this one where it asks the "estimated hours of use."
    So to reiterate the hours of use im supposed to be making up..?
  5. Oct 8, 2015 #4
    Yes, it seems. Sometimes you have to give some condition to solve an problem. Usually, people didn't watch the TV whole 7 days :)
  6. Oct 8, 2015 #5
    Hmm, it makes sense. But you would think that if I wasnt supposed to solve something that the estimated time would be an automatic given variable on the table.
  7. Oct 8, 2015 #6
    I read carefully the problem, but I didn't get it.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted