Heat Transfer MCQs

Metals are good conductors of heat because

Total heat is the heat required to

Moisture would find its way into insulation by vapor pressure unless it is prevented by

Cork is a good insulator because it has

The ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body. This statement is known as

Thermal conductivity of water in general with rise in temperature

An electric furnace has a laminated wall composed of 0.2 m of refractory brick (k=2), 0.15 m of insulation (k =0.15), and 0.15 m of brick having (k= 1.5). Inner and outer temperatures of wall are 1027°C and 27°C respectively. Units of k are kcal-m/hr m2 °C. If surface area of the wall is 1.2 m2, heat transfer rate will be

A steam pipe is to be insulated by two insulating materials put over each other. For best results

The ratio of emissive power of a body to the emissive power of a perfectly black body is called "