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A body having a surface area of 50cm^2 r...

A body having a surface area of `50cm^2` radiates 300J of energy per minute at a temperature of `727^(@)C`. The emissivity of the body is
( Stefan's constant`=5.67xx10^(-8)W//m^2K^4`)

A

0.09

B

0.018

C

0.36

D

0.54

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The correct Answer is:
B
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TARGET PUBLICATION-KINETIC THEORY OF GASES AND RADIATION -critical thinking
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  2. A spherical black body with a radius of 20 cm radiates 440 W power at ...

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  3. A body having a surface area of 50cm^2 radiates 300J of energy per min...

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  5. The rate of cooling at 600 K, if surrounding temperature is 300 K is R...

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  6. Two solid spheres of radii R(1) and R(2) are made of the same material...

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  7. A black body radiates 6 J//cm^2s when its temperature is 127 °C. How m...

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  8. The ratio of masses of two metal spheres A and B is 8 : I. If their te...

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  9. A hot liquid is kept in a big room. The logarithm of the numerical val...

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  11. A body cools at the rate of 0.75 °C/s, when it is 50 °C above the surr...

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  12. A body cools at the rate of 0.75 °C/s, when it is 50 °C above the surr...

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  13. A body takes 5 minutes for cooling from 50^(@)C to 40^(@)C Its temp...

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  14. Consider two hot bodies B(1) and B(2) which have temperature 100^(@)"C...

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  15. A body in laboratory takes 4 minutes to cool from 6 1 °C to 59 °C. If ...

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  16. A pan filled with hot food cools from 50 °C to 49.9 °C in 5 s. If it c...

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  17. A metal ball cools from 64^(@)C to 50^(@)C in 10 minutes and to 42^(@)...

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  18. A cup of tea cools from 80^(@)C to 60^(@)C in one minute. The ambient ...

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  19. The temperature of a body falls from 50^(@)C to 40^(@)C in 10 minute...

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  20. A body initially at 80^(@)" C" cools to 64^(@)" C" in 5 minutes and to...

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