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- Subject
- Heat Transfermechanical-engineering-mcqs › heat-transfer
- Published
- 24 Jan 2019
- Last updated
- 28 May 2026
Explanation
Here, a stands for absorptivity, p for reflectivity, and x for transmissivity. An object appears white when it reflects all incident radiation without absorbing or transmitting it, which corresponds to p = 1, x = 0, and a = 0.
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.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?
- 4.How do the thermal diffusivities of solids typically compare to those of liquids and gases?
- 5.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?
- 6.Under which conditions related to radiative properties is a body considered black?
- 7.The total emissive power refers to the total radiation energy emitted by a black body per unit of what?
- 8.A thermally transparent material reflects 40% of the incoming radiant energy on its surface. If the material's transmissivity is 0.15, what is the emissivity of its surface?
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