physics
posted by Anonymous .
There is a heat flow through a block of cross sectional area 21.5 cm2 and length 39 cm when the temperature difference of 18 degree Celsius is established across the block.
Find the rate of heat flow through the block, assuming it is made of aluminium with thermal conductivity k = 205 W/(m*K)
(kA) * (Change in T/change in x)
A is the crosssectional surface area,
ΔT is the temperature difference between the ends,
Δx is the distance between the ends

You have correctly written the formula. What is stopping you from pluggin in the numbers to get the answer? The units will be Watts. Make sure you use SI units (m^2, meters etc)