Q. A hollow sphere is rolling along a horizontal floor at 7.0 m/s when it comes to a 39^circ incline. How far does it go up the incline before coming to a stop and roll back down?
Q. A 22.00 g ball is fired horizontally with initial speed vi toward a 98-g ball that is hanging motionless from a 1.10 m long string. The balls undergo a head-on, perfectly elastic collision, after which the 100 g ball swings out to a maximum angle of θmax=45. What was vi?