Electricity is a strange magical thing... the realm of unicorns and leperchauns and such, no doubt. My kids and I were messing around w/ a little DC electric motor hooked up to an LED and spinning the motor which would induce current enough to light the LED. You could give the motor a good fast twist with your fingers, without a load, and it would spin an additional few rotations due to momentum. Hook up the LED and give it the same little spin and you could feel the difference and it would not free spin at all with a load - it took a whole lot more effort to get the LED to light. Being pretty ignorant in the field of electricity things started to click: you know, when a gas powered generator changes RPM's to account for additional load - it now made more sense experiencing it. Same for your vehicle's IAC valve needing to increase RPMs due to electrical loads.