Three identical cells with emf 1.5V and internal resistance 0.6 Ω each are connected in parallel. Find equivalent emf and internal resistance:
AE = 4.5V, r = 0.2 Ω
BE = 1.5V, r = 0.2 Ω
CE = 1.5V, r = 0.6 Ω
DE = 4.5V, r = 1.8 Ω
Answer & Solution
Correct answer: B. E = 1.5V, r = 0.2 Ω
In parallel with identical cells: E_eq = E (one cell) = 1.5V. r_eq = r/n = 0.6/3 = 0.2 Ω. Parallel keeps voltage but reduces internal resistance.
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