does the internal resistance of a battery decrease or increase power drain?
internal resistance
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I think I know the answer to this, example 9.1b (pg. 174 of the 2012 copy) in the TBR book explains this concept pretty well. The internal resistance decreases power drain to the circuit. The more the internal resistance reduced the amount of current, the more it decreases the power drain. This is your answer OP
I would like to hear a second opinion about this, since I believe since P=I^2R, this would show that increasing the resistance will lead to far less current. Since current is squared in the equation, the power drain would be reduced greatly. Or should I assume that since, "V= electromotive force - Ir" that if the internal resistance increases that this decreases the V. Since P=IV, this would mean that P would decrease as a result of decreasing V.
I would like to hear a second opinion about this, since I believe since P=I^2R, this would show that increasing the resistance will lead to far less current. Since current is squared in the equation, the power drain would be reduced greatly. Or should I assume that since, "V= electromotive force - Ir" that if the internal resistance increases that this decreases the V. Since P=IV, this would mean that P would decrease as a result of decreasing V.
yeah see my question arised from that statement in TBR book. Cause I dont see how logically increasing the internal resitance would decrease the power drain. I would think it should increase the power drain because thats just what resistance does....doesnt it?
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Yeah I see what you are saying, this is pretty much the limit of my knowledge on the subject. I don't think it does factor into R (the resistance due to a resistor), I think I am wrong about the whole P=I^2R thing and internal resistance. I think it is better to think about it from the stand point of V= emf - Ir. Ir is separate from the IR of a resistor altogether. This Ir would decrease the total voltage of the circuit. This would lead to a decrease in power in the equation P=IV. Sorry I couldn't help you anymore, you need the opinion of someone who has in-depth knowledge of the subject.
