Physics

Problem

A wall consists of a

5\,\text{cm}

layer of brick (

k=0.60\,\text{W m}^{-1}\text{K}^{-1}

) followed by a

2\,\text{cm}

layer of plaster (

k=0.20\,\text{W m}^{-1}\text{K}^{-1}

). The area of the wall is

1.0\,\text{m}^2

. The inner surface is at

35^\circ\text{C}

and the outer surface at

5^\circ\text{C}

. Calculate the steady heat loss per second through the wall. a)

2.1\times10^{2}\,\text{W}

1.6\times10^{2}\,\text{W}

3.6\times10^{2}\,\text{W}

1.1\times10^{2}\,\text{W}