# Homework Help: Physics C - Rotational motion/forces

1. Sep 7, 2008

### dominus96

1. The problem statement, all variables and given/known data

An amusement park ride consists of a rotating cylinder with rough canvas walls. The rider enters the cylinder and stands on the floor as the cylinder starts spinning, and as it spins, the floor lowers but the rider stays against the wall and does not slide down with it. The mass of the rider is 50 kg, the radius of the cylinder is 5 meters, the rotational speed is 2 radians/second, and the coefficient of static friction is 0.6.

a) Calculate the upward force that allows the rider from falling when the floor lowers, and state what provides that force.

b) At the same rotational speed, would a person of 100 kg slide down the wall? Explain.

2. Relevant equations

F=ma
Fcentripetal = mv2/r

3. The attempt at a solution

I drew a free-body diagram and got 500 N for weight, which would mean 500 N for friction since they are in opposite directions and the rider is in equilibrium. The normal force is 833 N.

For part a) I think the answer is the frictional force, but I don't know the exact reason.

Part b) I would assume that it won't affect it. Am I right?

2. Sep 7, 2008

### dominus96

bump can someone help me?