Answer:
[tex]\frac{dQ}{dt} = 966 W[/tex]
Explanation:
As we know that the rate of heat transfer due to temperature difference is given by the formula
[tex]\frac{dQ}{dt} = \frac{KA(\Delta T)}{L}[/tex]
here we know that
[tex]K = 0.69 W/m-K[/tex]
A = 4 m x 7 m
thickness = 30 cm
temperature difference is given as
[tex]\Delta T = 20 - 5 = 15 ^oC[/tex]
now we have
[tex]\frac{dQ}{dt} = \frac{(0.69W/m-K)(28 m^2)(15)}{0.30}[/tex]
[tex]\frac{dQ}{dt} = 966 W[/tex]