Determine the thermal conductivity of 4 in. (100 mm) of insulation with a unit conductance of
(a)
The thermal conductivity of insulation in English unit.
Answer to Problem 5.1P
The thermal conductivity of insulation in English unit is
Explanation of Solution
Given:
The unit conductance of insulation is
The thickness of insulation is
Formula used:
The thermal conductivity is given as,
Here,
Calculations:
The thermal conductivity can be calculated as,
Conclusion:
Therefore, the thermal conductivity of insulation in English unit is
(b)
The thermal conductivity of insulation in SI unit.
Answer to Problem 5.1P
The thermal conductivity of insulation in SI unit is
Explanation of Solution
Given:
The unit conductance of insulation is
The thickness of insulation is
Formula used:
The thermal conductivity is given as,
Here,
Calculations:
The thermal conductivity can be calculated as,
Conclusion:
Therefore, the thermal conductivity of insulation in SI unit is
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