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During radiation, having non conducting ...

During radiation, having non conducting medium between two surface may reduce transfer of heat.
Temperature at which person can feel metal rod and wooden block to be equally hot is

A

His body temeprature

B

Twice has body temperature

C

Four time equal to body temperature

D

Temperature equal to their ratio of specific heat capacities.

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BANSAL-HEAT TRANSFER-Exercise
  1. During radiation, having non conducting medium between two surface may...

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  2. During radiation, having non conducting medium between two surface may...

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  3. During radiation, having non conducting medium between two surface may...

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  4. The figure shows the face and interface temperature of a composite sla...

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  5. In the frame shown in figure made up of metallic rods of identical siz...

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  6. A ring consisting of two parts ADB and ACB of same conductivity k carr...

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  7. Spheres P and Q are uniformally constructed from the same material whi...

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  8. Calculate the quantity of heat conducted through 2m^(2) of a brick wal...

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  9. A black body emits 10 watts per cm^(2) at327^(@)C. The sun radiates 10...

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  10. A bulb made of tungsten filament of surface are a0.5cm^(2) is heated t...

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  11. A metal ball cools from 62^(@)C to 50^(@)C in 10min and to 42^(@)C the...

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  12. 0.15kg of water is filled in caloriemeter of copper with water equival...

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  13. At 1600K maximum radiation is emitted at a wavelength of 2mu(M). Then ...

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  14. For a temperature difference DeltaT=20.0^(@)C, one slab of material co...

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  15. When the air temperature is -10^(@)C, the ice on a large shallow lake ...

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  16. There slabs of thickness d(1), d(2), d(3) and thermal conductivites la...

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  17. Two rods of material, x and two of y are connected as shown in the fig...

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  18. A solid copper sphere (density =8900kgm^(-3) and specific heat C=390Jk...

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  19. The radiancy of a black body is M(e)=3.0W//cm^(2). Find the wavelength...

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  20. A thin wire of length l=50cm and area of cross-section S=3xx10^(-4)m^(...

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