if the man is simply in contact with the hollow cylinder, the direction of frictional force is indeterminate. the direction of frictional force is generally in the direction opposite to relative motion, and from the way the question is phrased (ie the man being simply in contact with the cylinder) it appears that frictional force is zero.
if not, please specify initial direction of motion of man.
Moderation Team
![[Post New]](/templates/default/images/icon_minipost_new.gif){kind=icon}
![[Up]](/templates/default/images/icon_up.gif "[Up]"){kind=icon}
47
