If two cells are connected in parallel as well as in series separately then in which case potential difference will be maximum and net internal resistance will be minimum

CONCEPT:

• Grouping of Cells: In a series grouping of cell’s their emf’s are additive or subtractive while their internal resistances are always additive.
• If dissimilar plates of cells are connected together then their emf’s are added to each other while if their similar plates are connected together then their emf’s are subtractive

EXPLANATION:

• Series grouping: In series grouping anode of one cell is connected to the cathode of other cells and so on.

• If n identical cells are connected in series

1. Equivalent emf of the combination E_eq = nE
2. Equivalent internal resistance r_eq = nr

• Parallel grouping: In parallel grouping, all anodes are connected at one point and all cathode are connected together at other points.

• If n identical cells are connected in parallel

1. Equivalent emf of the combination E_eq = E
2. Equivalent internal resistance r_eq = r/n

• Therefore, from above it is clear that the potential difference will be maximum in series combination and internal resistance will be minimum in parallel combination. Thus option 4 is correct.