Two conductors A and B each of cross section area 5 cm 2 are connected in series. Variation of temperature (in 0 C ) along the length (in cm) is as shown in the figure. If thermal conductivity of A is

Question

Two conductors A and B each of cross section area $5 cm^{2}$ are connected in series. Variation of temperature (in $^{0} C$ ) along the length (in cm) is as shown in the figure. If thermal conductivity of A is $200 J / m - sec^{0} C$ and thermal conductivity of B (in $J / m - sec^{0} C$ upto one decimal place.) is k then find $\frac{k}{8 3}$ .

TestHub · Accepted Answer

The same steady heat current flows through both rods, and their cross-sectional areas match.
$K_{A} \frac{d T}{d x}_{A} = K_{B} \frac{d T}{d x}_{B}$
$200 tan 6 0^{\circ} = K_{B} tan 4 5^{\circ}$
$K_{B} = 2003$
$\frac{K _{B}}{8 3} = \frac{200 3}{8 3} = 5$
Answer 5.

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