JEE Mains · Physics · STD 12 - 3. current electricity
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 _________ \(\Omega\).
- A \( (\sqrt{3}-1)R \)
- B R
- C \( 2(\sqrt{3}-1)R \)
- D \( (\sqrt{3}+1)R \)
Answer & Solution
Correct Answer
(A) \( (\sqrt{3}-1)R \)
Step-by-step Solution
Detailed explanation
\( \frac{(2R+x).(R)}{3R+x}=x \) \( x^{2}+2Rx-2R^{2}=0 \) \( x=(\sqrt{3}-1)R \)
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