A cubical box of volume 216cm3 is made up of 0.1 cm thick wood. The inside is heated electrically by a 100 W heater. It is found that the temperature difference between the inside and the outside surface is 5∘C in steady state. Assuming that the entire electrical energy spent appears as heat, find the thermal conductivity of the material of the box.

A cubical box of volume 216cm3 is made up of 0.1 cm thick wood. The in

1.	A cubical box of volume 216cm3 is made up of 0.1 cm thick wood. The inside is heated electrically by a 100 W heater. It is found that the temperature difference between the inside and the outside surface is 5∘C in steady state. Assuming that the entire electrical energy spent appears as heat, find the thermal conductivity of the material of the box.
Answer» A cubical box of volume $216 c m^{3}$ is made up of 0.1 cm thick wood. The inside is heated electrically by a 100 W heater. It is found that the temperature difference between the inside and the outside surface is $5^{\circ} C$ in steady state. Assuming that the entire electrical energy spent appears as heat, find the thermal conductivity of the material of the box.

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