NTA Abhyas JEE Main2020PhysicsCurrent ElectricityPractice
Two cells having internal resistance 0 . 2 Ω and 0 . 4 Ω are connected in parallel with the same polarity. The voltage across the battery terminals is 1 . 5 V . If the emf of the first cell is 1 . 2 V , then what is the emf of the second cell (in volt)?
Correct answer
2.1
Step-by-step solution
Given that, the resultant voltage across the battery terminal= 1 . 5 V Clearly, 1 . 2 Volt Battery is Charging and another battery is discharging given, 1.2 + 0.2 I = 1.5 ⇒ I = 3 2 A E - 0.4 I = 1.5 ⇒ E = 1.5 + 0.4 × 3 2 ⇒ E = 2.1 V