Circular Motion (high school level)

[SigFig]

Homework Statement

The carnival ride shown in Figure 7-18 has a 2.0 m radius and rotates once each .90 s

a. Find the speed of the rider.
b. Find the centripetal acceleration of the rider.
c. What produces this acceleration?
SOLUTIONS PROVIDED:
a. 141
b. 98
c. --Explain--

Homework Equations

ac=v^2/r
T=1/f
Fc=m(4pi^2r/T^2)

The Attempt at a Solution

I apologize for not using script, I was having a bit of difficulty. However, this is what I got.
.90=v^2/2
√v
=1.34
Completely wrong, please help.

 

[rock.freak667]

You didn't really provide a diagram, so I am assuming it is one of those rotating cylinder things.

For the speed of the rider, it tells you that the ride rotates ever 0.9s,, can you figure out the angular velocity from this? Given that you found that and have the radius, how do you get the velocity v from these two quantities?