How Fast Can a Merry-Go-Round Spin Before a Child Slides Off?

[cheddahchad]

Homework Statement

A child with mass m = 30 kg is sitting on a 12-m diameter merry-go-round. What is the maximum speed the merry-go-round can travel and the child not slide with a static friction coefficient of 0.56?

Homework Equations

To be honest, I had to miss a day of class because I was sick. I have no idea where to start on this problem. Any help or formulas would be much appreciated!

The Attempt at a Solution

See #2

 

[haruspex]

It's about centripetal force. If you really haven't heard of that or don't know any equations concerning it, search the net. Calculate the centripetal force required to keep the child from spinning off, then use your usual statics equations to determine the frictional force, the normal force, and thus the minimum coefficient of static friction.