When a battery of emf 8 V with internal resistance 0.5 Ω is charged by a 120 V DC supply using a series resistance of 15.5 Ω , then what is the terminal voltage (in volt) of the battery?

Step-by-step solution

Here, emf of the battery = 8 V The internal resistance of the battery, r = 0.5 Ω The voltage of D. C supply = 120 V External resistance, R = 15.5 Ω When the battery of emf 8 V is charged from a DC supply of 120 V , the effective emf in the circular is ε = 120 - 8 = 112 V The total resistance of the circuit = R + r = 15.5 + 0.5 Ω = 16 Ω ∴ Current in the circuit during charging I = ε R + r = 112 16 = 7 A ∴ The terminal voltage of the battery, V = e m f o f t h e b a t t e r y + v o l t a g e d r o p a c r o s s t h e