Physics · PYQ NEET UG 2018
हिन्दीA set of 'n' equal resistors, of value 'R' each, are connected in series to a battery of emf 'E' and internal resistance 'R'. The current drawn is I. Now, the 'n' resistors are connected in parallel to the same battery. Then the current drawn from battery becomes \( 10\text{ I} \). The value of 'n' is Which of the above statements is/are correct?
Correct answer · Option A
10
Explanation
In series: \( I = \frac{E}{nR + R} \). In parallel: \( 10I = \frac{E}{\frac{R}{n} + R} \). Dividing the two equations: \( \frac{1}{10} = \frac{R/n + R}{nR + R} = \frac{1/n + 1}{n + 1} = \frac{1+n}{n(n+1)} = \frac{1}{n} \implies n = 10 \).