Servo's and EduBots?

[DanL]

I finally got access to the actual servo, so I was able to look up the specs (as well as realize the edubattery is 7.2v, not 9v... oops). Anyways, the specs for the servo's say they're rated between 4.8v and 6v, so I need to drop the voltage a bit. The problem is I've never actually done these calculations, so I need some help.

Ohm's law solved for resistance is R = E / I, or Resistance = Voltage / Amperage. Now, I have a few questions... do I use the voltage supplied, or the voltage I want to have? The latter seems kinda silly, so I'm guessing E is the voltage supplied. As for amerage, the servo specs list two opperating currents: 7.7mA @ 6v for "Idle Current" and 180mA @ 6v for "Running Current". One gets a resistance of 935 ohms, and the other gets a resistance of 40 ohms. So the question is which do I use? I'm guessing I use the higher amerage, because thats the limit and the motor can go less if it need to, but like I said, I've never done this, so all of this is a complete guess.

What I'm basically asking is to hook the servo's up to the 7.2 volt EduBot pwm ports, is the resistor I need to use 40ohm?