Please give proper reason of each step of your solution with suitable diagram .(don't give links )
21. A 70 kg man stands in contact against the inner wall of a hollow cylindrical drum of radius 3m rotating about its vertical axis with 200 rev/min. The coefficient of friction between the wall and his clothing is 0.15. When the floor is suddenly removed, what is the minimum rotational speed of the cylinder to enable the man to remain stuck to the wall without falling (approximately) ?
