A small button placed on a horizontal rotating platform with diameter 0.295 m will revolve by the platform when it is brought up to a speed of 30.0 rev/min, provided the button is no more than 0.132 m from the axis.
a) What is the coefficient of static friction among the button and the platform?
b) How far from the axis can the button be placed, without slipping, if the platform rotates at 45.0rev/min?