The flywheel of a punching machine has a mass of 300 kg and a radius of gyration of 600 mm. Each punching operation requires 2500 J of work.
(a) Knowing that the speed of the flywheel is 300 rpm just before a punching, determine the speed immediately after the punching.
(b) If a constant 25 N-m couple is applied to the shaft of the flywheel, determine the number of revolutions executed before the speed is again 300 rpm.