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4 years ago

6

Yasir is trying to build an energy-efficient wall and deciding what materials to use. How can he calculate the thermal resistanc

e of the wall?
A. It's the mean layer thermal resistance.
B. It's equal to the least thermally resistant layer.
C. Add the thermal resistance of its layers.
D. Measure the thermal loss.

1 answer:

777dan777 [17]4 years ago

8 0

Answer:

Add the thermal R values of each wall layer.

Explanation:

Fiberglass insulation R value, sheetrock, sheathing, siding etc. All sum together to one composite opposition to heat transfer/loss.

Q= U x A x Delta T

Q= heat transfer btuh

U= 1/R inverse of resistance

A= area of surface

Delta T is temerature difference across the wall.

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Now putting the all values

$h=\dfrac{0.0048\times 15\times 1.43^2}{2\times 9.81\times 0.05}+\dfrac{0.0058\times 24\times 0.63^2}{2\times 9.81\times 0.075}+0.5\dfrac{1.43^2}{2\times 9.81}$

So h=0.23 m

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3 years ago

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<u>Explanation</u>:

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