In alternating current, how often does the current alternate between negatively and postively?

Aflywheel accelerates for 5 seconds at 2 rad/s2 from a speed of 20 rpm. determine the total number of revolutions of the flywheel during the period of its acceleration. a.5.65 b.8.43 c. 723 d.6.86

How to increase the thermal officiency of an ideal simple rankino cycle? among these methods, which one is the best and why?

Agas is compressed from vi 0.3 m, p 1 bar to of v2 0.1 m3, p2--3 bar. pressure and volume are related linearly during the process. for the gas, find the work, in kj.