How do digital volt meters work? If I connect a Digital voltmeter to a battery, how does it measure the voltage. And i'm assuming it measures terminal voltage, not emf? This question's probably simple but it's been bugging me for awhile. All I can think of is that the DVM produces (or measures maybe?) a current, and then because of the internal resistor it measures the drop in voltage? (which would explain why the DVM has to be in parallel). Then the drop in voltage somehow = the voltage of the battery? (that's that part that would make the least sense to me, if the rest of my theory is right). But I'm probably way off, so can someone explain it to me?