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A 100 watt filament loses all its power ...

A 100 watt filament loses all its power by radiation, when it is heated to a temperature 2500 K. If the diameter of the filament is 0.2mm and emissivity of the filament is 0.5, find the length of the filament to (`sigma = 5.67 xx 10^-8 J//m^2sK^4`)

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A 100 watt filament loses all its power by radiation when it is heated to a temperature of 2500 K. If the diameter of the filament is 0.2 mm and the surface emissivity of the filament is 0.5, find the length of the filament. (Stefan's constant sigma = 5.67 xx10^-8 W/m^2k^4 )

A 60 watt filament lamp loses all its energy by radiation from its surface. The emissivity of the surface is 0.5. The area of the surface is 5 xx 10^-5m^3 . Find the temperature of the filament ( sigma = 5.67 xx 10^-8m^2s^-4K^-4 )

The temperature of the filaments of a 100W electric lamp is 2727^@C . The emissivity of the surface of the filament is 0.086 and its radius is 0.5 mm. Find the length of the filament. sigma = 5.7 xx 10^-8 S.I. units.

Energy is emitted from a hole in an electric furnace at the rate of 20W when that temperature of the furnace is 727^@C . What is the area of the hole ( sigma = 5.7 xx 10^-8 Js^-1m^-2K^-4 )

A filament of an evacuated light blue has length 10 cm, diameter 0.2mm and emissivity 0.2. Calculate the power it radiates at 2000 K ( sigma=5.67xx10^-8 J/m^2k^4 )

A metal ball of surface area 200 cm^(2) and temperature 527^(@)C is surrounded by a vessel at 27^(@)C . If the emissivity of the metal is 0.4, then the rate of loss of heat from the ball is (sigma = 5.67 xx10^(-8)J//m^(2)-s-k^(4))

Calculate the energy radiated in one minute by a black body of surface area 100 cm^2 when it is maintained at 227^@C ( sigma= 5.67 xx 10^-8 J/m^2sK^4 )

A copper sphere has a surface area of 3.142 xx 10^-2m^2 and its emissivity is 0.018. Find the energy lost by the sphere per second when its temperature is 100^@C . ( sigma = 5.67 xx 10^-8 W/m^2k^4 .)

The length of a rod is 0.5 xx 10^(2) m , the order of magnitude of the length of the rod is

CHETANA PUBLICATION-Kinetic Theory of Gases and Radiation-Exercise
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  2. 16 gm of oxygen occupied 0.025 m^3 at 27^@C. It the universal gas cons...

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  3. A cylinder filled with hydrogen gas at 500 K exerts a pressure of 4 at...

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  4. The velocities of three molecules of a gas are 2m//s,3m//s and 4 m//s,...

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  5. Calculate the R.M.S. velocity of helium at temperature 0^@C (density o...

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  6. At what temperature can the R.M.S. velocity of gas be three times its ...

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  7. Calculate the number of molecules in one litre of gas at N.T.P., if ma...

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  8. Find the mass of 10c.c of gas at N.T.P. if RMS.velocity of gas molecul...

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  9. Find the KE per kg of nitrogen molecule at 127^@C (molecular weight of...

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  10. Calculate the R.M.S. velocity of oxygen molecule at N.T.P., if the den...

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  11. If the R.M.S. velocity of oxygen molecules at N.T.P. is 460 m//s, dete...

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  12. The ratio of molar specific heats of certain gas is 1.4, if molar spec...

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  13. Compare the R.M.S. velocity of hydrogen molecules at 400 K with R.M.S....

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  14. Radiant energy is incident on the body at a rate of 1500 J//min. If co...

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  15. Radiant energy is incident on the body at a rate of 1500 J//min. If co...

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  16. Radiant energy is incident on the body at a rate of 1500 J//min. If co...

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  17. A metal cube of each side 0.05 m long emits 0.6k cal in 80 seconds, Ca...

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  18. The emissive power of sphere of area 0.02 m^2 is 0.5 kcal//s-m^2. What...

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  19. The coefficient of absorption of a surface is 0.6. When radiant energy...

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  20. Assuming that the sun radiates as a black body, calculate the energy r...

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  21. The temperature of the filaments of a 100W electric lamp is 2727^@C. T...

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