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A polished metal plate with a rough blac...

A polished metal plate with a rough black spot on it is heated to about `1400K` and quickly taken into dark room Then .

A

The spot will appear brighter that the plate

B

the spot will appear darker than the plate

C

the spot and the plate will appear equally bright

D

the spot and the plate will not be visible in the dark room

Text Solution

Verified by Experts

The correct Answer is:
A
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NIKITA PUBLICATION-KINETIC THEORY OF GASES & RADIATION -MCQs (Perfectly black body, emmissive power and emmissivity)
  1. The phenomenon of black body radiation was explained satisfactorily by

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  2. An electric heater kept in vacuum is heated continuously by passing el...

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  3. A polished metal plate with a rough black spot on it is heated to abou...

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  4. A man with a dark skin, in comparison with a man with a white skin, wi...

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  5. If the temperature of a perfectly black-body increases two times then ...

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  6. A ferfectly black body is one which absorbs radiation of

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  7. Reflectance of a perfectly black body is

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  8. Good absorbers of heat are

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  9. The maximum energy emitted per unit time per unit area by a body for a...

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  10. Coffee cools faster in saucer than in cup because of

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  11. The ratio of spectral emissive power of a body lamda and temperature T...

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  12. The spectrum from a black body radiation is a

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  13. A perfectly black body in one whose emissivity is

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  14. The emissive power of a surface depends upon

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  15. A perfectly white body

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  16. The amount of heat energy radiated per second by a surface depends upo...

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  17. S.I unit of emissive power is

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  18. Below a list of four types of surfaces

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  19. The silver polishing the walls of a thermos bottle minimizes the trans...

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  20. The bulbs of two identical thermometers are coated one with lamp black...

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