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- Subject
- Heat Transfermechanical-engineering-mcqs › heat-transfer
- Published
- 24 Jan 2019
- Last updated
- 28 May 2026
Explanation
The Prandtl number for air is typically around 0.7, which represents the ratio of momentum diffusivity to thermal diffusivity in the fluid.
More Heat Transfer MCQs
Practice related questions from the same subject.
- 1.According to Wien's displacement law, the wavelength at which a blackbody emits maximum radiation is directly related to which of the following?
- 2.Under what condition, based on radiative characteristics, is a material considered opaque?
- 3.Under which condition based on radiative characteristics does an object appear white?
- 4.Which principle states that the ratio of a body's emissive power to its absorptive power is constant for all materials and equals the emissive power of an ideal black body?
- 5.How do the thermal diffusivities of solids typically compare to those of liquids and gases?
- 6.According to Stefan's law, the total energy radiated per second per unit area by a black body is directly proportional to which of the following?
- 7.Under which conditions related to radiative properties is a body considered black?
- 8.The total emissive power refers to the total radiation energy emitted by a black body per unit of what?
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