Five identical cells, each of emf E and internal resistance r , are connected in series to form a closed loop. If one of the cells is connected with reverse polarity, what is the terminal potential difference across this reversed cell?

Step-by-step solution

Let the five cells be connected in a closed loop. Four cells are connected in the same direction, while one is reversed. The net emf driving the current in the loop is the difference between the aiding emfs and the opposing emf: E_ net = 4E - E = 3E The total internal resistance of the five cells in series is: R_ total = 5r The current I flowing in the loop is: I = E_ net R_ total = 3E 5r For the reversed cell, the current enters its positive terminal, meaning it is being charged. The terminal potential difference