A 12m times 14m house is bull on a 12 cm thick concrete slab

A 12m times 14m house is bull on a 12 cm -thick concrete slab part A What is the heat-loss rale through the slab if the ground temperature is 8 ^degreeC while the of the houses 21 ^degreeC? Express your answer to two significant figures and include the appropriate units.

Solution

A = 168 m² , x = 0.12 m

dense concrete = 1.40 W/m*K

H = delta Q / delta t = k * A * delta t / x

delta T = 21 - 8 = 13

H = 1.4 * 168 * 13 / 0.12

= 25480 W = 25.4 kW