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Power usage

  1. Mar 25, 2007 #1

    barneygumble742

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    hi,

    the attached image is from the back of my laptop.

    i'm trying to figure out how much watts it consumes per hour.

    i know that power is current multiplied by volts. so its 90.09 watts = 4.62 amps * 19.5 volts. is this the watts per hour?

    thanks,
    mark
     

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    barneygumble742, Mar 25, 2007
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  3. Mar 25, 2007 #2

    Averagesupernova

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    I'm not sure, but the 4.62 amps may be what it takes to run the laptop as well as charge a low battery. It may not take this much current all of the time. Once the battery is charged current consumption probably drops off.
     
    Averagesupernova, Mar 25, 2007
  4. Mar 25, 2007 #3

    dlgoff

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    "...is this the watts per hour?"

    This is the amount of power consumed. The energy from 90 watts for one hour is 90 watt-hours; for two hours is 180 watt-hours.
     
    dlgoff, Mar 25, 2007
  5. Mar 25, 2007 #4

    sunday

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    And you have to take in account the efficiency of the power brick, usually in the range of 90%, so the total power will be around 100.1 W
     
    sunday, Mar 25, 2007
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