Could somebody explain in a very easy way (with a drawing of what goes to what) show how one measures how many amp a motor is taking?
I found the Lego motors (I presume you're into the NXT or RCX style motors rather than teh old circa 1980s ones?) to be massively efficient. Strange as it sounds, they don't behave like coils at all.
Have you ever hooked two of them back-to-back and turned the spindle of one? Of course it acts as a generator, but the "slave" motor turns with an almost 1:! ratio!!
I find that reasonably strange.
I think you can just use a clip-on meter. It simply clamps around the positive wire -it's inductive. Double check what you get, though -some will only work with AC.