A small button placed on a horizontal rotating platform with diameter 0.326m will revolve with the platform when it is brought up to a rotational speed of 43.0rev/min , provided the button is a distance no more than 0.145m from the axis.
Part A: What is the coefficient of static friction between the button and the platform?
Part B: How far from the axis can the button be placed, without slipping, if the platform rotates at 55.0re.