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Homework Help: Heating Element

  1. Sep 21, 2010 #1
    Hi ,

    I have a question thats confusing and difficult to comprehend

    " A heating element is placed on the floor and bag of water is placed over it. At present, A power of 300W is applied to the heating element. Peter, the technician, wants to increase the rate at which the water in the water bag is heated up. What should peter do to increase the rate?"

    assuming the current supplied and the voltage across the heating element are not changed, reducing the resistance would do the trick. but reducing the resistance can be done only by changing the heating element . kind of confused...

    Can someone help?
     
  2. jcsd
  3. Sep 21, 2010 #2

    Lok

    User Avatar

    Questions...

    Is heat loss of the water considered?

    Is the floor a perfect insulator?

    Is this a electronics problem, or thermodynamics? (usually the answer should be in a specific domain for a vaguely given problem.)

    Is the current DC or AC? ( Very important to know).
     
  4. Sep 21, 2010 #3
    its an AC current, floor- perfectly insulated, and assuming there is no heat loss from water...
     
  5. Sep 21, 2010 #4
    you can reduce the amount of water.......
     
  6. Sep 21, 2010 #5

    Lok

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    If AC current what other variables are there that Peter can play with, and what is their effect.
     
  7. Sep 21, 2010 #6
    I said"you can reduce the amount of water" .........I AM SERIOUS
     
  8. Sep 21, 2010 #7

    Lok

    User Avatar

    Don't be.

    This is a AC phys problem so all other ways... like breathing hot air onto it, or hitting it with a bat to hopefully create life that is able to evolve cold fusion is not an option.
     
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