A body radiates heat at the ate of 5 cal/m2-s when its temperature is 227°C. the heat radiated by the same body when its temperature is 727°C is
10 cal/m2-s
20 cal/m2-s
40 cal/m2-s
80 cal/m2-s
Additional Questions
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Which one of the following constants is not related to radiation? |
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Rate of cooling of body is 0.5°C/min, when the system is 50°C above the surroundings. When a system is 30°C above the surroundings, the rate of cooling will be |
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According to Wien’s law |
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The sun emits light with a maximum wavelength of 510 nm while another star X emits light of maximum wavelength of 350 nm. What is the ratio of the surface temperatures of the sun and the star? |
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A sphere cube and a thin circular plate all made of the same material and having the same mass are initially heated to a temperature of 300°C. which of these cools fastest? |
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A black body emissive power is 81 J/m2 sec it is at 300 K another one ordinary body emissivity is 0.8 it is at 500 K then what is the emissive power of ordinary body? |
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Which one of the following constants is related to radiation? |
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The temperature of a piece of metal is raised from 27°C to 51.2°C. the rate at which metal radiates energy increases nearly |
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If a black body is heated from 27°C to 927°C. then the ratio of radiation emitted will be |
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You are given a sphere, a cube and a thin circular plate, all made from copper and all having the same mass. If they are heated to a temperature of 200°C, then which are of them will cool fasted? |
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