You are on the Turkish Twist, an amusement park ride with your back against the wall of a spinning vertical cylinder of radius 4.0 m. The floor falls away and yet you are somehow held against the wall. Assume that your mass is 70 kg, and that the coefficient of static friction between you and the wall is 0.55.
(a) What is the minimum number of revolutions per minute necessary to prevent you from sliding down the wall?
(b) Would this answer change if you were considering your little brother, who has a mass of 35 kg? Explain.