![]() After all, their (and our) lives and livelihoods literally depend on it. ![]() For their part, electricians understand electromotive force and current perfectly well. This draw/pull stuff is more electrician-speak than engineering, though plenty of engineers use these terms too. And the more parallel loads (resistances) you add, the more the load, or ‘draw’, from the supply. So we might say a resistor will ‘draw/pull 10A on this branch’ meaning it will ‘load this branch 10A’. You have this resource - power - and you’re taking some of it from a source and using it to do something. One ‘draws’ water from a well, so by that analogy one ‘draws’ power from a power source. ‘Pull’ is synonymous with ‘draw’ in this context, and they both mean ‘load the circuit’, even though we know that electric charge is both ‘pushed’ and ‘pulled’ through a load (like a resistor) by potential difference, that is, electromotive force.ĭraw/pull goes with the ‘water analogy’ of electricity. ‘Drawing’ or ‘pulling’ current or power are figures of speech. So why does adding more resistors result in more current being pulled? This seems to imply that resistors have a "pulling" force to draw electrons, which they definitely do not (since the whole point of a resistor is to resist the flow of electrons, right?).īut this answer does make sense. The rest of the answer uses Ohm's law to explain why the parallel resistors must therefore have a certain equivalent resistance. 1mA will flow through 1 resistor and 1 mA will flow through the other resistor. Again apply 10V and you will see that 2 mA (not 1 mA as before) is drawn. Now consider that there are TWO resistors inside and that they are in parallel. ![]() If you have a "black box" with two wires connected and are told that there is a resistor inside you could measure voltage applied and current drawn to determine the internal resistance. One of the answers involved simulating parallel resistors as a black box and it made sense. I was looking at an explanation for why parallel resistors have less resistance: ![]()
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