JEE Mains · Physics · STD 12 - 3. current electricity
Two conductors have the same resistances at \(0^{\circ} \mathrm{C}\) but their temperature coefficients of resistance are \(\alpha_1\) and \(\alpha_2\). The respective temperature coefficients for their series and parallel combinations are _______.
- A \(\alpha_1+\alpha_2, \frac{\alpha_1+\alpha_2}{2}\)
- B \(\frac{\alpha_1+\alpha_2}{2}, \frac{\alpha_1+\alpha_2}{2}\)
- C \(\alpha_1+\alpha_2, \frac{\alpha_1 \alpha_2}{\alpha_1+\alpha_2}\)
- D \(\frac{\alpha_1+\alpha_2}{2}, \alpha_1+\alpha_2\)
Answer & Solution
Correct Answer
(B) \(\frac{\alpha_1+\alpha_2}{2}, \frac{\alpha_1+\alpha_2}{2}\)
Step-by-step Solution
Detailed explanation
Series : \(R_{e q}=R_1+R_2\) \(2 R\left(1+\alpha_{e q} \Delta \theta\right)=R\left(1+\alpha_1 \Delta \theta\right)+R\left(1+\alpha_2 \Delta \theta\right)\) \(2 R\left(1+\alpha_{\mathrm{eq}} \Delta \theta\right)=2 R+\left(\alpha_1+\alpha_2\right) R \Delta \theta\)…
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