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Homework Help: Covert to Watts, Input and Output Values provided, Covert it to Watts

  1. Mar 21, 2012 #1
    I have this Sony Laptop, the adapter has the following specifications:

    These are the input and output values of laptop charger.

    19.5V written in bold on top
    Input:100-240V~1.3A 50-60Hz
    Output: 19.5V---4.7A, the dotted line also has straight line above it, I dont know whats that symbol called, can someone help me in calculating how much watts it is?
  2. jcsd
  3. Mar 21, 2012 #2


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    welcome to pf!

    hi raokhan! welcome to pf! :smile:
    ~ (as you know) means AC, and that no-overtaking double-line means DC :wink:

    for DC, power (in watts) = volts times amps (W = VA),

    so in this case the output power is 19.5*4.7 W :smile:

    (but i don't know how much extra power is consumed by the charger itself :confused: … chargers can get rather warm!)
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