Question:
Four cells (emf E, internal resistance r) are connected in series, but one is wrongly connected. Find the equivalent emf and internal resistance.
Four cells (emf E, internal resistance r) are connected in series, but one is wrongly connected. Find the equivalent emf and internal resistance.
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Emf subtracts for reverse connection, resistance adds in series.
Updated On: Feb 16, 2025
- 4E and 2r
- 4E and 3r
- 3E and 4r
- 2E and 4r
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The Correct Option is D
Solution and Explanation
Correct connection: 3E. Incorrect connection: -E. Total emf: 3E - E = 2E. Total internal resistance: 4r (sum of individual resistances).
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