COMEDK · Physics · 19. Current Electricity
A battery is made of 12 cells having emf \(5 \mathrm{~V}\) each. If three cells are unknowingly connected wrong, the resultant emf of the battery will be:
- A 90V
- B 45V
- C 30V
- D 60V
Answer & Solution
Correct Answer
(C) 30V
Step-by-step Solution
Detailed explanation
The total number of cells is \(n = 12\). Each cell has an emf \(E = 5 \text{ V}\). When all cells are connected in series correctly, the total emf is \(nE = 12 \times 5 = 60 \text{ V}\). If \(x\) cells are connected with wrong polarity, these \(x\) cells will cancel out the emf…
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