Find the closest ambient temperature

A fireclay brick cube, 10 cm in length is removed from a furnace where it was maintained at a temperature of 500 degrees C. The brick cube is then placed in ambient temperature conditions. The heat flow from the brick is 400 Watts. The closest ambient temperature is: a) 300 deg C. b) 200 deg C. c) 100 deg C. d) 0 deg C.

Illustration of Heat flow ,temperature gradient and thermal conductivity relation

A 4 m diameter sphere is embedded in insulation. The sphere contains a liquid-ice mixture maintained at 0 deg C. The ambient temperature surrounding the insulation is 25 deg C. The heat loss is 400 W. What is the temperature conductivity of the insulation? a) Less than 0.5 W/m-deg C b) 0.5 to 1.0 W/m-deg C c) Greater than 2 W/m-deg C d) none of the above

Determine Fourier Number

Compare two identical steel spheres, except the first has a two inch diameter while the second sphere has a four inch diameter. The larger sphere will have a Fourier number approximately: a) half that of the smaller sphere b) four times larger than that of the smaller sphere c) twenty-five percent of the value of that of the smaller sphere d) the Fourier numbers will be identical

Determine heat flow

Heat flow through a uniform wall will: a) increase as the thermal resistance increases b) increase as the thickness of the wall increases c) decrease as the thermal differences on each side of the wall increases d) decrease as the thermal resistance increases

Determine shape factor

A thin disk is maintained at 75 deg C and placed on the surface of a large medium maintained at 10 deg C. The thermal conductivity of the medium is 1.4 W/m-deg C, and there is a heat loss of 36 W. The shape factor, S is closest to: a) 20 cm b) 40 cm c) 60 cm d) 80 cm