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 cross-sectional 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)
To find the rate of heat flow through the block, we can use the formula:
Rate of heat flow = (-kA) * (Change in T/change in x)
Where:
k is the thermal conductivity of the material (in this case, aluminum with k = 205 W/(m*K))
A is the cross-sectional surface area (in this case, A = 21.5 cm^2 = 0.00215 m^2)
Change in T is the temperature difference between the ends (in this case, ΔT = 18 degrees Celsius)
Change in x is the distance between the ends (in this case, Δx = 39 cm = 0.39 m)
Now, let's substitute these values into the formula:
Rate of heat flow = (-205 W/(m*K)) * (0.00215 m^2) * (18 degrees Celsius / 0.39 m)
After performing the calculations, we would get the rate of heat flow through the block in watts.