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Finding the currrent of the circuit

  1. Jul 14, 2011 #1
    1. The problem statement, all variables and given/known data
    What is the current in the circuit shown in the figure for the following? (Let R = 1 Ω and V = 12 V. Calculate the total current drawn from the battery.)

    1. what is the current when the switch is closed

    3. The attempt at a solution
    i had to find the current when the switch is open which is easy because it's just two series which are parallel which turn in to one series

    but when it's closed it is really confusing i've tried to do it several ways but i cannot determine which way i can do it. i tried adding the R1 and 5 ohms first using parallel but it wouldn't work. can you tell me a way to add the resistors?
    thank you
  2. jcsd
  3. Jul 14, 2011 #2
    When it's closed, the bottom R and 1 are in parallel. Same as top R and 5. Then add up their resistances.
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