An extremely hot star would appear to be
When a black body is heated, it emits heat radiations of |
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A black body is at 300 K. It emits energy at a rate which is proportional to |
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An ideal black body is represented by |
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The coefficient of transmission and coefficient of reflection for a given body at a given temperature are 0.33 and 0.64 respectively. Then the coefficient of emission of the same body at the same temperature will be |
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If a black body is heated from 27°C to 927°C, then the ratio of the radiation emitted by the body at the two temperatures will be |
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The correct equation out of the following is |
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Two sphere of same material have radii r1 and r2. They are heated to same temperature and kept in same enclosure at low temperature their rates of loss of heat are in the ratio |
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If the wavelengths of maximum intensity of radiation emitted by the moon and the sun are 10–4 m and 0.5 × 10–6m respectively, then the ratio of their temperature is |
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The maximum wavelength of radiation emitted by a black body at 1227°C is λm. What is its maximum wavelength at 2227°C? |
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A black body radiates energy at the rate of E watt m–2 at a temperature of T Kelvin. When the temperature is reduced to T/2 Kelvin, the radiant energy will become |
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