COMEDK · Physics · 12. Thermal Properties of Matter
Two rods of same area of cross-section and lengths and conductivities \(K_{1}\) and \(K_{2}\) are connected in series. Then in steady state, conductivity of the combination is
- A \(\left(K_{1}+K_{2}\right) /\left(K_{1} K_{2}\right)\)
- B \(2 K_{1} K_{2} /\left(K_{1}+K_{2}\right)\)
- C \(\left(K_{1}+K_{2}\right) / 2\)
- D \(K_{1} K_{2} /\left(K_{1}+K_{2}\right)\)
Answer & Solution
Correct Answer
(B) \(2 K_{1} K_{2} /\left(K_{1}+K_{2}\right)\)
Step-by-step Solution
Detailed explanation
The thermal resistance of a rod is given by \(R=\frac{l}{K A}\) As, length and area of two rods are same, then in series combination,…
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