Questions on cells in parallel and cells in series

Two identical cells whether connected in parallel or in series gives the same current, when connected to an external resistance 1.5Omega . Find the value of internal resistance of each cell.

Five cells each of emf E and internal resistance r send the same amount of current through an external resistance R whether the cells are connected in parallel or in series. Then the ratio ((R)/(r)) is

Two resistance connected in parallel across a cell of negligible internal resistance, use 4.5 times the power that they would use, when in series across the same cell. If one of the resistance is 8ohm, the other is:-

Cells in series |Cells in parallel

When two identical cells are connected either in series or in parallel across a 4 ohm resistor, they send the same current through it. The internal resistance of the cell in ohm is

For what basic purpose the cells are connected (i) in series (ii) in parallel and (iii) in mixed grouping?

When cells are arranged in series