JEE Mains · Physics · STD 12 - Current electricity
- JEE Mains 2023
- Medium
- MCQ
Equivalent resistance between the adjacent corners of a regular \(n\)-sided polygon of uniform wire of resistance \(R\) would be:
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(\frac{(n-1) R}{n^2}\)
Step-by-step Solution
Detailed explanation
Suppose resistance of each arm is \(r\), then \(r = R / n\)
\(R _{ eq(AB )}=\frac{ R _1 R_2}{R_1+R_2}\)
\(\frac{ r ( n -1) r }{ r +( n -1) r }\)
\(=\frac{ r ( n -1) r }{ nr }\)
\(=\frac{ n -1}{ n } r\)
\(=\frac{( n -1) R }{ n ^2}\)
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