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Power of a hot plate and actual heat power delivered

  1. Dec 2, 2011 #1
    Hey Guys,

    I really did my best to locate the best sub-forum for my question (I was hesitating between the Homework one and this one), so please bear with me if my choice is wrong ...

    Now to my question: So in my kitchen, I have a hot plate appliance, and it says on it that power consumption is 1200 Watt. Now what I am confused about is what does this power truly represent, especially that the hot plate has a knob that you can turn to control the plate's temperature. I mean, isn't the choice of temperature going to influence the actual heating power of the plate ? And if so, what are the parameters that I need to know that actual power ?

    Thanks :)
  2. jcsd
  3. Dec 2, 2011 #2


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    Staff: Mentor

    That is the peak/rated output. Yes, it can vary with the setting.

    Finding the actual relationship can only be done experimentally.
  4. Dec 2, 2011 #3
    Thank you so much for your answer. Is a linear relationship expected between the actual power consumption and the temperature that I set on the hot plate ?
  5. Dec 2, 2011 #4
    "Is a linear relationship?"

    If you have a pot of cold stew on the hot plate, the relationship is close to linear. If the stew is boiling, the temperature is mostly independent of setting. If there's nothing on the hot plate, then heat is being dissipated through a combination of radiative transfer (proportional to Temp^4) and free or forced convection (also non-linear, but complicated).
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