JEE Mains · Physics · STD 12 - Current electricity
- JEE Mains 2026
- Hard
- MCQ
Two known resistance of \(R \Omega\) and \(2 R \Omega\) and and one unknown resistance \(X \Omega\) are connected in a circuit as shown in the figure. If the equivalent resistance between points A and B in the circuit is \(X \Omega\), then the value of X is _________ \(\Omega\).

Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \( (\sqrt{3}-1)R \)
Step-by-step Solution
Detailed explanation
\( \frac{(2R+x).(R)}{3R+x}=x \)
\( x^{2}+2Rx-2R^{2}=0 \)
\( x=(\sqrt{3}-1)R \)
\( x^{2}+2Rx-2R^{2}=0 \)
\( x=(\sqrt{3}-1)R \)
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