An aluminium bar is 3.25m long and has a diameter of 25mm. if the temperature difference between the ends is 250°c, find the rate of heat transfer along the bar. (where the thermal conductivity for al is 205w/m°c) is it 5.67 w, 7.74 w, or 10.5 w?

Answer

7.74 W

Explanation

The formula for getting the the rate of heat transfer is:

=

A = πr² = π×(12.5/1000)²

            = 4.908×10⁻⁴m²

Rate of heat transfer   =

                                      = 7.74 W

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