Atmospheric air is in parallel flow (u=10 m/s, to= 15°c) over a flat heater surface that is to be maintained at a temperature of 90°c. the heater surface area is 0.25 m^2, and the airflow is known to induce a drag forde of 0.15 n on the heater. what is the electrical power needed to maintain the prescribed surface temperature?

Explain the difference laminar and turbulent flow. explain it with the shear stress and the velocity profiles.

An open feedwater heater operates at steady state with liquid entering at inlet 1 with t? = 40°c and pl = 1 .2 mpa. water vapor att2-200°c and p2 = 1.2 mpa enters at inlet 2. saturated liquid water exits with a pressure of pa 1.2 mpa. neglect heat transfer with the surroundings and all kinetic and potential energy effects, determine the mass flow rate of steam at inlet 2 if the mass flow rate of liquid water at inlet 1 is given as 2 kg/s.

A5 kg block of fe is dropped into a very large vat of water. the fe and water initial temperatures are 95 and 25 c, respectively. the fe final temperature is 25 c and the water can be treated as a thermal reservoir,. treated as a thermal reservoir take the water to be the system and determine the entropy generation. report vour answer in kj/k.