WBJEE · Physics · Current Electricity
Consider the circuit shown in the figure.
The value of the resistance \(X\) for which the thermal power generated in it is independent of small variation of its resistance is
- A \(X=R\)
- B \(X=\frac{R}{3}\)
- C \(X=\frac{R}{2}\)
- D \(X=2 R\)
Answer & Solution
Correct Answer
(C) \(X=\frac{R}{2}\)
Step-by-step Solution
Detailed explanation
For above circuit \[ \begin{array}{l} \frac{1}{R^{\prime}}=\frac{1}{R}+\frac{1}{X}=\frac{R+X}{R X} \\ R^{\prime}=\frac{R X}{R+X} \end{array} \] The current in the circuit \(i=\frac{E}{R+R^{\prime}}=\frac{E}{\left(R+\frac{R X}{R+X}\right)}\)…
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