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How to find the current and equivalent resistance in a parallel circuit

  1. Mar 1, 2009 #1
    1. The problem statement, all variables and given/known data

    Three 16 ohm resistors are connected in parallel and placed across a 34 V battery.
    (a) What is the equivalent resistance of the parallel circuit?
    (b) What is the current delivered by the battery?

    2. Relevant equations

    (a) (1/equivalent resistance) = 1/R1+1/R2+1/R3+...
    (b) I=V/R

    3. The attempt at a solution

    (a) (1/16)+(1/16)+(1/16) = (3/16)
    equivalent resistance = (3/16)
    (b) (34 V / 48 ohm) = .7917 amps
  2. jcsd
  3. Mar 1, 2009 #2
    For resistors in parallel we have that:

    1/R_{total} = 1/R_1+1/R_2+1/R_3 + \ldots,

    so you need to take the inverse of the result you gave.

    For (b), use the answer from (a) and the expression you correctly wrote: I = V/R.
  4. Mar 1, 2009 #3


    User Avatar
    Gold Member

    Compare your a) relevant equation to your a) solution attempt. There is something very simple missing.

    b) You must find the correct resistance in part a) to solve.

    Edit- Niles beat me
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