What is the process for changing the polarity on a DC machine? A. Current cannot be changed
B. Turn machine off and back on again
C. Change location of cables
D. Switch electrodes

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

Afluid flows with a velocity field given by v=(x/t)i.. determine the local and convective accelerations when x=3 and t=1.

An engine runs on the ideal diesel cycle. the cycle has a compression ratio of 20 and a cutoff ratio of 2. the highest temperature in the cycle is 1200 k. if the heat into the system is 300 kj/kg of working fluid and using variable specific heats determine the work produced per mass of working fluid