In a circuit, the cell p has an emf 1.5Vand an unknown internal resistance while the cell Q has an emf 2.0V and an internal resistance 1. If the ammeter reads 50mA what is R?

Internal resistance for cell p is .

Explanation:

From the Question,

Emf of cell p & q are and respectively. Internal resistance of cell q is .

Current reads by ammeter is .

So, According to question

Applying Ohm's law

                       Where    I - Current

                                    V- Voltage

                             And R- Resistance

then,

                                                             {∵ }

Therefore , Internal resistance for cell P is 9 ohm.