Adisk-shaped merry-go-round of radius 3.03 m and mass 125 kg rotates freely with an angular speed of 0.661 rev/s . a 59.4 kg person running tangential to the rim of the merry-go-round at 3.51 m/s jumps onto its rim and holds on. before jumping on the merry-go-round, the person was moving in the same direction as the merry-go-round's rim.

Explanation:

given,  

radius of merry - go - round = 3.03 m  

mass of the disk = 125 kg  

speed of the merry- go-round = 0.661 rev/s

speed = 3.51 m/s  

mass of person =59.4 kg  

initial angular momentum of the system  

final angular momentum of the system  

from conservation of angular momentum  

answer; equivalent to a one(1) horsepower motor;