oursmon $3(40$ percent$)$

A refroctory brick of size $6cm9cm20cm$ at $1400C$ is exposed suddenty to convection at $30C$

with $h$:$60\frac{W}{m}2K.$ Determine the center temperature, comer temperatures and temperoture at the center point of all faces after $45$ minutes. Also colculote the total heat flow via:

$\frac{Q}{Q_1}=\frac{Q_2}{Q_h}+\frac{Q_2}{Q_n}[1-\frac{Q_i}{Q_n}]+\frac{Q_2}{Q_0}[1-\frac{Q_2}{Q_n}][1-\frac{Q_2}{Q_n}]$

Properties: k: $1\frac{W}{m}K,$ density: $2645k\frac{g}{m^3}.$ Specific heat : $960\frac{J}{k}gK.$