COMEDK · Physics · 19. Current Electricity
Ten cells, each having internal resistance \(1 \Omega\) and emf 1.5 V are connected in series. But unknowingly 3 cells are connected wrongly in series. The effective internal resistance and emf of the series combination are respectively:
- A \(10 \Omega\) and 6 V
- B \(10 \Omega\) and 15 V
- C \(6 \Omega\) and 10 V
- D \(0.1 \Omega\) and 1.5 V
Answer & Solution
Correct Answer
(A) \(10 \Omega\) and 6 V
Step-by-step Solution
Detailed explanation
The total number of cells is \(n = 10\). Each cell has an emf \(E = 1.5\) V and internal resistance \(r = 1 \Omega\). When cells are connected in series, the total internal resistance is the sum of individual resistances, regardless of their polarity. Thus, the effective…
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