JEE Mains · Physics · STD 12 - 3. current electricity
The balancing length for a cell is \(560 \;\mathrm{cm}\) in a potentiometer experiment. When an external resistance of \(10 \;\Omega\) is connected in parallel to the cell, the balancing length changes by \(60\; \mathrm{cm} .\) If the internal resistance of the cell is \(\frac{\mathrm{N}}{10} \;\Omega,\) where \(\mathrm{N}\) is an integer then value of \(\mathrm{N}\) is
- A \(12\)
- B \(10\)
- C \(8\)
- D \(14\)
Answer & Solution
Correct Answer
(A) \(12\)
Step-by-step Solution
Detailed explanation
\(\mathrm{r}=\mathrm{R}\left(\frac{\mathrm{x}-\mathrm{x}^{\prime}}{\mathrm{x}^{\prime}}\right)\) \(=10 \times \frac{60}{500}\) \(=12\)
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