There are 200cells of emf 2v and internal resistance 1ohm. There are m rows having n cells in each row. If the combination have a net emf of 50v. Then find m,n and internal resistance ?

Answer:
See below
Explanation:
Each parallel row = 50 v so there is 25 cells in each (2 v each)
200 cells / 25 cells / row = 8 rows of 25 cells each
the equivalent resistance is
each row has resistance = 25 ohms
equivalent resistance =
1 / ( 8 * 1/25) = 3.125 ohms