A. Yellow paint
B. White paint
C. Black paint
D. Grey paint
Correct Answer: Black paint ✔
Last Updated: March 03, 2019
Related MCQs
- Three materials A, B and C of equal thickness and of thermal conductivity of 20, 40 & 60 kcal/hr. m. °C respectively are joined together. The temperature outside of A and C are 30°C and 100°C respectively. The interface between B and C will be at a temperature of __________ °C?
- The thermal radiation emitted by a body is proportional to Tn, where T is its absolute temperature. The value of ‘n’ is exactly 4 for__________?
- Evaporation by thermo compression results in the __________?
- Use of transverse baffles in a shell and tube heat exchanger is done to increase the__________?
- Which of the following situations can be approximated to a steady state heat transfer system ?
- Heat transfer by __________ may not necessarily require the presence of a medium?
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- Prandtl number is the reciprocal of__________?
- For a multipass shell and tube heat exchanger, the LMTD correction factor is always__________?
- Thermal conductivity of a gas at low density, __________ with increase in temperature ?
- The interchange factor for radiation heat transfer from surface ‘x’ to surface ‘y’ in case of an infinite parallel planes with emissivities εx & εy is given by__________?
- With increase in temperature, the thermal conductivity of a gas __________?
- Which area is used in case of heat flow by conduction through a cylinder ?
- The rate of emission of radiation by a body does not depend upon the__________?
- In a cooling tower, water becomes cool by__________?
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- The overall resistance for heat transfer through a series of flat resistance, is the __________ of the resistances?
- Heat transfer co-efficient equation for forced convection, Nu = 0.023 Re 0.8. Pr n, is not valid, if the value of __________?
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- The units of resistance to heat transfer is __________?
- For hot feed, forward feeding as compared to backward feeding results in __________ economy?
- In sub-cooled boiling ?
- Heat transfer by conduction results due to the transfer of free electrons, kinetic energy & vibrational energy from one molecule to another. Conduction heat transfer cannot take place__________?
- The thickness of condensate layer in filmwise condensation depends on the__________?
- The heat transfer co-efficient in film type condensation is __________ that for dropwise condensation?
- Steam economy in case of a triple effect evaporator will be __________?
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- The Graetz number is concerned with the__________
- The unit of conductance in SI unit is__________?
- Which of the following has the lowest Prandtl number ?
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- Stefan-Boltzmann law which describes the radiation heat transfer states that, it is proportional to (where, t = temperature in °C T = absolute temperature in ° K) ?
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