Answer:
68.75W
Step-by-step explanation:
Heat transfer is describe as the flow of thermal energy as a result of changes in temperature between two or more bodies. Heat transferred via solid bodies is called conduction, and that associated with liquids and gases is called convection, and likewise, the one attributed to electromagnetical waves is called radiation.
heat transfer from the tube wall to the water = kA.ΔT
= 3500* π* (2.5 * 10⁻²)²/4 *40
= 68.75W