There is a sweet potato with an initial uniform temperature of 25 c and it has an average diameter of 70 mm. thermal conductivity and diffusivity of the potato are 0.62 w/m c and 0.2 x 10^-6 m^2/s. respectively. it is to be cooled by refrigerated air at 1.8°c flowing at a velocity of 4 m/s. the average heat transfer coefficient between the potato and the air is 25 w/m2·°c. determine how long it will take for the center temperature of the potato to drop to 5.5°c

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

Afour cylinder four-stroke in-line engine has a stroke of 160mm, connecting rod length of 150mm, a reciprocating mass of 3kg and its firing order is 1-3-4-2. the spacing between cylinders is 100mm. i. show that the engine is in balance with regard to the primary inertia forces and primary 3. a and secondary inertia couples. li determine the out of balance secondary inertia force ii. propose ways of balancing this out of balance force and discuss the challenges that will arise

Air is compressed isentropically from an initial state of 300 k and 101 kpa to a final temperature of 1000 k. determine the final pressure using the following approaches: (a) approximate analysis (using properties at the average temperature) (b) exact analysis