Why does a voltage drop in a circuit create higher amps!???
I'm a HD mech apprentice and I don't understand this!! I was taught in school that if you hook up a 12V battery to a light you will have 5 amps. add a resistor you will have .5 amps. Totally random number choices but what I mean is the more resistance the less amps. NOW I'm being told that in a machine if the battery is low and you go to start it you could blow the starter because the low voltage causes high amps. which yes I understand watts so the less voltage you have the more amps to do the same work. But since you have less supply voltage how the hell is it sending you more?? and in a normal circuit aswell. I was told that the more voltage drop you have from too much resistance the more amps??? WTF!! WHAT AM I MISSING HERE?!
by 
HDMech
ANSWERS: 1
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I think you need to think about the component that is causing the effect rather than the entire circuit. A battery is a fixed-voltage DC power supply. As the battery starts to run out of electrolyte, the battery's internal resistance increases, so the voltage output drops, but, if the internal resistance increases faster than the output voltage decreases, the output current has to increase to compensate (Ohm's Law: V = IR). This is further driven by the circuits call for constant power (P = IV) at a reduced voltage. Thus, the battery will supply more current if it is able to do so, leading to possible over-current of other circuit components.
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