# Potentiometer Resistance

1. Sep 23, 2007

### tanky322

1. The problem statement, all variables and given/known data
In the circuit below, the wiper divides the potentiometer resistance between $$\alpha R$$ and$$\ (1- alpha R)$$, 0 $$\leq$$$$\alpha$$ $$\geq 1$$. Find Vo / Vs

2. Relevant equations

KVL
KCL

3. The attempt at a solution

Im thinking that the Pot. Resistance will be R +(1-$$\alpha$$)R. Then to find the voltage (R +(1-$$\alpha$$)R)I

#### Attached Files:

• ###### Schematic1.JPG
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2. Sep 23, 2007

### mgb_phys

You can ignore the resistance of the main part of the pot to ground that is below the wiper because it is in parallel with a short circuit.
The resitance of the pot is simply, R - alphaR = R(1-alpha)

3. Sep 24, 2007

### tanky322

(($$\Sigma$$R)/I)Vs