Problem: A fairground ride called "The Wall of Death" consists of a cylindrical container of internal diameter 6.50m, mounted on a cylindrical axis. The passengers feel as if they are being pushed against the wall as the container begins to rotate. Eventually, the floor is lowered, leaving the miserable passengers pinned to the wall, apparently defying gravity. When the ride slows down, the passengers just begin to slide down the wall when they are rotating at 0.400 revolutions per second.
Part A: Calculate the coefficient of static friction between the wall and the passengers' backs.
I want help to find the coefficient of static friction between the wall and the passengers' backs.