_ The critical thickness of insulation for a sphere is$?

1.	_ The critical thickness of insulation for a sphere is$?
A.	k/h‚Äö√á√Ñ
B.	2k/h‚Äö√á√Ñ
C.	h‚Äö√á√Ñ/k
D.	h‚Äö√á√Ñ/2k
Answer» C. h‚Äö√á√Ñ/k

Discussion

No Comment Found

Related MCQs

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
Two long parallel surfaces each of emissivity 0.7 are maintained at different temperatures and accordingly have radiation heat exchange between them. It is desired to reduce 75% of the radiant heat transfer by inserting thin parallel shields of emissivity 1 on both sides. The number of shields should be
According to Stefan Boltzmann law, the total radiation from a black body per second per unit area is directly proportional to the
In counter current flow heat exchanger, the logarithmic temperature difference between the fluids is ________ as compared to parallel flow heat exchanger.
The engine oil at 150 degree Celsius is cooled to 80 degree Celsius in a parallel flow heat exchanger by water entering at 25 degree Celsius and leaving at 60 degree Celsius. Estimate the number of transfer units
After being in service for a period of six months, a heat exchanger transforms 10% less heat than it does what new. Determine the effective fouling factor in terms of its clean overall heat transfer coefficient. It may be presumed that the heat exchanger operates between the same temperature differentials and that there is no change in the effective surface area due to scale build up
What is the value of specific heat for Bakelite in J/kg K?
In a food processing plant, a brine solution is heated from – 12 degree Celsius to – 65 degree Celsius in a double pipe parallel flow heat exchanger by water entering at 35 degree Celsius and leaving at 20.5 degree Celsius. Let the rate of flow is 9 kg/min. Estimate the area of heat exchanger for an overall heat transfer coefficient of 860 W/m² K. For water c P = 4.186 * 10³ J/kg K
What is the value of specific heat for brick in J/kg K?
A counter flow heat exchanger is used to col 2000 kg/hr of oil (c p = 2.5 k J/kg K) from 105 degree Celsius to 30 degree Celsius by the use of water entering at 15 degree Celsius. If the overall heat transfer coefficient is expected to be 1.5 k W/m² K, find out the water flow rate. Presume that the exit temperature of the water is not to exceed 80 degree Celsius

_ The critical thickness of insulation for a sphere is$?

Discussion

No Comment Found

Related MCQs

Reply to Comment