# Homework Help: Wheastone Bridge

1. Mar 19, 2014

### kexanie

1. The problem statement, all variables and given/known data
Compute i1 and i2 in Figure a). R3 = R4 = 6Ω, and R5 = R6 = 12Ω.

2. Relevant equations

KVL and KCL

3. The attempt at a solution

Since R3 / R5 = R4 / R6 , it's a Wheastone Bridge and i2 = 0, and i1 = $\frac{20}{9}$ A.

But my question is, why circuit in Figure b) is not equivalent to circuit in Figure a) when a) is a Wheastone Bridge?

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Last edited: Mar 19, 2014
2. Mar 20, 2014

### ehild

The current through the vertical wire between the two pairs of parallel resistances is not equal to I2. Consider the Nodal Law. What is I2 in a) and what is it in b). Are they identical?

ehild