Out of 100 kcal/second of incident radiant energy on the surface of a thermally transparent body, 300 kcal/second is reflected back. If the transmissivity of the body is 0.25, the emissivity of the surface will be

Related MCQs

• 40% of incident radiant energy on the surface of a thermally transparent body is reflected back. If the transmissivity of the body be 0.15, then the emissivity of surface is
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• The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe whose surface temperature remains constant is
• Depending on the radiating properties, a body will be white when (where a = absorptivity, p = reflectivity, x = transmissivity)
• Depending on the radiating properties, a body will be black when (where a = absorptivity, p == reflectivity, X = transmissivity.)
• Depending on the radiating properties, a body will be opaque when (where a = absorptivity, p = reflectivity, X = transmissivity.)
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