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itsmarasilly
Mar1-09, 03:48 PM
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

Niles
Mar1-09, 04:01 PM
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.

S_Happens
Mar1-09, 04:02 PM
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