JEE Mains · Physics · STD 12 - 3. current electricity
A wire of resistance \(R\) is bent to form a square \(ABCD\) as shown in the figure. The effective resistance between \(E\) and \(C\) is ( \(E\) is mid-point of arm \(CD\) )

- A \(\frac {1}{16}R\)
- B \(\frac {7}{64}R\)
- C \(\frac {3}{4}R\)
- D \(R\)
Answer & Solution
Correct Answer
(B) \(\frac {7}{64}R\)
Step-by-step Solution
Detailed explanation
\(\frac{1}{R_{e q}}=\frac{8}{7 R}+\frac{8}{R}\) \(\frac{1}{R_{e q}}=\frac{8+56}{7 R} ; \quad R_{e q i}=\frac{7 R}{64}\)
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