In question number 3, the thermal conductivity (in `W m^(-1) K^(-1)`) if air isA. `1/10`B. `1/12`C. `1/14`D. `9/130`

In question number 3, the thermal conductivity (in `W m^(-1) K^(-1)`)

1.	In question number 3, the thermal conductivity (in `W m^(-1) K^(-1)`) if air isA. `1/10`B. `1/12`C. `1/14`D. `9/130`
Answer» Correct Answer - C The temperature difference across the plate. `DeltaT_("plate") = ((dQ)/dt)xx (l_("plate"))/(K_("plate") xx A) = (65 xx 4 xx 10^(-3))/(1 xx 1.3) = 0.2 K` `:. DeltaT_("air") = 13 - 2DeltaT_("plate") = 12.6 K` `K_("air") = (((dQ)/(dt))xxl_("air"))/(ADeltaT_("air")) = (65 xx 18 xx 10^(-3))/(1.3 xx 12.6) = 1/14 W m^(-1) K^(-1)`

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In question number 3, the thermal conductivity (in `W m^(-1) K^(-1)`) if air isA. `1/10`B. `1/12`C. `1/14`D. `9/130`

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