The thermal conductivity of a sheet of rigid, extruded insulation is reported to be k=0.029 w/m. k. the measured temperature difference across a 25-mm-thick sheet of the material is latex: t_1-t_2\: =\: 12°ct 1 − t 2 = 12 ° c . a) what is the heat flux (in w/m2) through a 3m by 3m sheet of the insulation?

flux=13.92W/m^2

Explanation:

The heat transfer by conduction consists in the transport of energy through particles that are together, that is to say by means of solids, Newton developed an equation that allows to know the heat transported in a flat plate knowing the cross sectional area A, Thickness L, conductivity  K  and a temperature difference between the internal and external surface.

Q=KA(t2-t1)/L

To know the heat flux we simply divide both sides of the equation by the area.

Flux=K(t2-t1)/L

where

K=0.029w/mk

L=25mm=0.025m

t2-t1=12 ° C

solving

Flux=(0.029)(12)/(0.025)

flux=13.92W/m^2

the answer would be a