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Homework Help: Energy from a 60-watt bulb

  1. Dec 21, 2005 #1
    I'm not sure I'm doing this correctly...

    If all of the energy from a 60-watt bulb was put into 1 gram of water at room temperature for 2 seconds, how much would the temperature of the water increase?

    I tried it using the example but I wanted to check my answer first.

    60 * 2 = 120
    120 / 4.1868

    29 degrees Celsius?
     
  2. jcsd
  3. Dec 21, 2005 #2
    That's correct; nice work.

    Don't be afraid to show the formulae you use, though.
     
  4. Dec 21, 2005 #3
    Ah, that's good.:smile:

    Actually, I don't know the formula. I was using the example on this site http://ippex.pppl.gov/interactive/energy/calorie.html" [Broken].
     
    Last edited by a moderator: May 2, 2017
  5. Dec 21, 2005 #4
    [tex]P = \frac{\Delta E}{\Delta t} \Rightarrow \Delta E = P \Delta t[/tex]

    [tex]\Delta E = mc \Delta T[/tex]

    They're a little useless if you've never covered the concept, though, I suppose.
     
    Last edited: Dec 21, 2005
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