Circular Motion and carnival ride

AI Thread Summary
The discussion revolves around calculating the maximum rotation period of a vertical cylinder amusement park ride that keeps a person pressed against the wall due to centrifugal force. Given the parameters, including gravity, the coefficient of static friction, and the cylinder's radius, the initial attempt to find the period T resulted in an incorrect value. The correct approach involves ensuring that the frictional force equals the gravitational force acting on the person. Clarification is sought on whether the frictional force should equal the person's weight, indicating a need for further understanding of the forces involved.
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Homework Statement


An amusement park ride consists of a large vertical cylinder that spins about its axis fast enough that a person inside is stuck to the wall and does not slide down when the floor drops away. The acceleration of gravity is 9.8m/s^2.
Given g=9.8 m/s^2, the coefficient of static friction between the person and the wall = 0.337. The radius of the cylinder, R=5.8m. For simplicity, neglect the person's depth and assume he or she is just a physical point on the wall. The person's speed is v= (2{pi}R)/T where T is the rotation period of the cylinder (the time to complete a full circle).
Find the maximum rotation period T of the cylinder which would prevent a 47kg person from falling down. Answer in units of seconds.

*For clarity this ride is one that spins and the person is pressed against the wall*
-attached is an image of the ride-

Homework Equations



v= (2{pi}R)/T
Ff=(coefficient of friction)(Fn)
Ff=m*((v^2)/R)

The Attempt at a Solution


M=coefficient of Friction
m=mass

Ff=M(Fn)
Ff=(0.337)(460.6)
Ff=155.22

Ff=m*((v^2)/R)
155.22=47*v^2/5.8
v=4.3766m/s^2

v= (2{pi}R)/T
4.3766=2{pi}(5.8)/T
T=8.326 seconds

-this answer is wrong-
 

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Almost - you are trying to find what normal force is needed so that the frictional force is equal to their weight.
 
Thanks for the reply.

However, I am still confused as to what I need to do.

Does Ff=47?
 
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Thread 'A cylinder connected to a hanging mass'
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