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Homework Help: Circuits with schemes

  1. Feb 3, 2009 #1
    1. The problem statement, all variables and given/known data
    The manufacturer of a 12V car headlight specifies it will draw a current of 6A. You would like to check this claim with an ammeter designed to measure currents up to 10A and having a resistance of 0.1 Ohms. Which of the two figures below represents a circuit where the ammeter correctly measures the current in the headlight?
    a). How much current (in A) would flow in the ammeter for Circuit a?
    b.)How much current (in A) would flow in the ammeter for Circuit b?

    2. Relevant equations
    delta(V) = IR

    3. The attempt at a solution

    Circuit a should be the ammeter measurement
    a.)I = 12/0.1 = 120
    b.)I = 12/.01 = 120
  2. jcsd
  3. Feb 3, 2009 #2


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    Science Advisor
    Homework Helper

    Hi dasblack! :smile:

    Yes, circuit a.

    But you haven't used the resistance of the headlamp

    what should you assume it is (from the manufacturer's specification)? :wink:
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