Consider a House That Is Approximated as a Cube That$20 ^ { \circ } \mathrm { C }$

Question

Examlex · Accepted Answer

The Answer is The total surface area is

5 imes ( 8 \mathrm {~m} imes 8 \mathrm {~m} ) = 320 \mathrm {~m} ^ { 2 }

Equation (8.5) gives the power loss as

P = A \Delta T / R

or

R = A \Delta T / P

So for

\Delta T = 40 ^ { \circ } \mathrm { C }

and

P = 5000 \mathrm {~W}

then the

R

-value is

R = \left( 320 \mathrm {~m} ^ { 2 } ight) imes \left( 40 ^ { \circ } \mathrm { C } ight) / ( 5000 \mathrm {~W} ) = 2.56 \mathrm {~m} ^ { 2 } \cdot { } ^ { \circ } \mathrm { C } / \mathrm { W }

Consider a House That Is Approximated as a Cube That $20 ^ { \circ } \mathrm { C }$