I'm ordering components for my board, and I'm wondering what value would be appropriate for a linear pot. It will be used to take power from the 5V supply, and then pass to the analog in to convert to digital values.

I'm having trouble finding out how much current the 5V pin can output.

Because voltage is changing, current would remain constant through the pot (if I understand correctly).

Using V=IR I get the following. (I'm assuming a current of 50mA)

R=V/I

if V=0 and I=0.05A, then R=0

if V=5 and I=0.05A, then R=100

I made a graph to see if it would help me understand:

This seems counterintuitive though, because if I were to pass the 5V source right to the analog in I believe that the resistance would be 0 (not accounting for the resistance of the wire). According to the formula 0 resistance should give me 0V.

If anyone can tell me what I'm doing horribly wrong it would be greatly appreciated.