Part A A 39.0 g ball is fired horizontally with initial speed vo toward a 100 g ball that is hanging motionless from a 1.10 m -long string. The balls undergo a head-on, What was vo? perfectly elastic collision, after which the 100 g ball Express your answer with the appropriate units. swings out to a maximum angle 0max = 50.0 0 ? Value s Units Submit Request