Two sphere of the same material have radii 1 m and 4 m and temperature 4000 K and 2000 K respectively. the energy radiated per second by the first sphere is
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A surface at temperature $T_{0}$ K receives power P by radiation from a small sphere at temperature T >> T0 and at a distance d. If both T and d are doubled, the power received by surface will becomes approximately |
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If temperature of a black body increases from 7°C to 287°C, then the rate of energy radiation becomes |
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A bucket full of hot water is kept in a room and it cools from 75°C to 70°C in $t_{1}$ minutes from 70°C to 65°C in $t_{2}$ minutes and from 65°C to 60°C in $t_{3}$ minutes; then |
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A sphere, a cube and a thin circular plate, all made of the same material and having the same mass are initially heated to a temperature of 3000 K, which of these will cool fastest? |
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Which of the following is most repaid process |
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Two spheres made of same material have radii in the ratio 2:1. if both the spheres are at same temperature, then what is the ratio of heat radiation energy emitted per second by them? |
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A perfectly black body emits radiation at temperature $T_{1}$ K. If it is to radiate 16 times this power, its temperature $T_{2}$. will be |
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Unit of Stefan’s constant is given by |
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The flow of heat from a hot body to a cold body is an example of |
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For which of the following process, the thermal conduction is maximum? |
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