Connor lifts a 1,500 N barbell above his head from the floor to a height of 2m. He holds the barbell there for 5 sec.
a. How much work does he do lifting the barbell?
B. How much work does he do during the 5 second interval?

The 10-kg double wheel with radius of gyration of 125mm about o is connected to the spring of stiffness k = 600 n/m by a cord which is wrapped securely around the inner hub. if the wheel is released from rest on the incline with the spring stretched 225 mm, calculate the maximum velocity v of its center o during the ensuing motion. the wheel rolls without slipping

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?

Am i correct on these two physics questions?