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Homework Help: Simple domestic electricity

  1. Mar 11, 2010 #1
    A current of 0.25A flows through a bulb when a voltage of 12V is applied across it. Calculate the power and resistance of the bulb.

    please show working out
     
  2. jcsd
  3. Mar 11, 2010 #2

    tiny-tim

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    Welcome to PF!

    Hi hgo0! Welcome to PF! :wink:

    Show us what you've tried, and where you're stuck, and then we'll know how to help! :smile:
     
  4. Mar 11, 2010 #3
    0.25A x 12V = 3W

    i dont know how to get the resistance or if im doing this right :uhh:
     
  5. Mar 11, 2010 #4

    tiny-tim

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    Hi hgo0! :smile:

    That's right: amps times volts = watts (or current times voltage = power).
    Have you done Ohm's Law (or Kirchhoff's rules ) ? If not, look them up.

    V = IR (or potential difference = voltage = current times resistance). :wink:
     
  6. Mar 11, 2010 #5
    kk thanks alot i'm new to physics (first year) and failing soo i need all the help i can get :biggrin:
     
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