Three identical cells, each of internal resistance R, are connected in series with an external resistor of resistance R. The current in the external resistor is I. If one of the cells is reversed I'm the circuit, what is the new current in the external resistor? (In terms of I and R)
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Can someone please help me with this question? I have no idea how to deal with reversed cells, I know the total resistance is going to be 4R and the current is constant throughout the entire circuit, but that's as far as I've gotten.