"NEVER connect an ammeter in parallel!!!" -->WHY?! Why must an ammeter never be connected in parallel, or across the terminals of a power source? All I know about this is that you'll blow a fuse if you connect an ammeter in parallel... but I don't know why you'd blow a fuse. My guess: The current that you'd measure if the ammeter was connected in series would be the current that had gone through the resistor, so the current would be lower than the current coming straight out of the power supply. This un-resisted (?) current is too high for the ammeter to bear. If you could help me on this, I'd be so grateful! THANK YOU!