Physics-
General
Easy
Question
Window A is a plane sheet of glass 4 millimeters thick, as shown. Window B is a sandwich consisting of two extremely thin layers of glass separated by an air gap 2 millimeters thick, as shown. If the thermal conductivities of glass and air are 0.8 watt/meter°C and 0.025 watt/meter°C, respectively, then the ratio of the heat flow through window A to the heat flow through window B for same temperature difference from 
and for same time duration T sec area is same for window A and B.
- 2
- 4
- 8
- 16
The correct answer is: 16
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