umw an. u... 3.3 Centripetal Force a (a) A 22.0kg child is riding a playground merry-go-round' that is rotating: at 40.0 revfmin. What centripetal force is exerted if he is 1.25 m from its center? (b) What centripetal force is exerted if the me-ny-go-round rotates at 3.00 rev/min and he is 8.00 m from its center? (c) Compare each farce with his weight. 56. Calculate the centripetal force on the end of a 1oo-m (radius'l wind turbine blade that is mmna at n 5