WBJEE · Physics · Thermal Properties of Matter
Two rods of equal length and diameter have thermal conductivities 3 and 4 units respectively. If they are joined in series, the thermal conductivity of the combination would be
- A \(3.43\)
- B \(3.5\)
- C \(3.4\)
- D \(3.34\)
Answer & Solution
Correct Answer
(A) \(3.43\)
Step-by-step Solution
Detailed explanation
In series \(R=R_1+R_2\) \(\begin{aligned} & \frac{2 \ell}{K_{e f f} A}=\frac{\ell}{K_1 A}+\frac{\ell}{K_2 A} \\ & K_{e f f}=\frac{24}{7}=3.43\end{aligned}\)
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