The observation that will be noticed in transferring heat by changing the intermediate cross sectional area is that;
An increase in the intermediate cross sectional area would lead to an increase in the rate of heat transfer and vice versa.
dQ/dt = kA(dT/dx)
Where;
dQ/dt is rate of heat transfer
k is thermal conductivity of the medium
A is cross sectional area
dT/dx is the rate of change of the temperature per unit length
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