MHT CET202525 Apr 2025Evening ShiftPhysicsCurrent ElectricityActual
Two batteries of e.m.f 4 V and 8 V with internal resistance 1 and 2 respectively are connected in a circuit with a resistance of 9 as shown in the figure. The current and potential difference between the points ' P ' and ' Q ' is
Options
- A1 3 ~A and 4 V
- B1 3 ~A and 3 V
- C1 2 ~A and 5 V
- D1 6 ~A and 3 V
Correct answer
B. 1 3 ~A and 3 V
Step-by-step solution
Net circuit EMF: Batteries in series with opposing polarities yield E_ net = 8 - 4 = 4 V , with direction determined by the larger EMF source. Total resistance: All resistances including internals are in series: R_ total = 1 + 2 + 9 = 12 . Current calculation: Applying Ohm's law, I = 4 12 = 1 3 A . Potential difference V_ PQ : This equals the voltage drop across the external resistor: V_ PQ = 1 3 9 = 3 V . The calculated values correspond to option B .