A block is rotating in contact with vertical wall (rotor) as shown. Find the minimum value of `omega` so that the block does not slide down.

Explanation

Here the necessary centripetal force is provide by normal reaction.
`N=momega^(2)R`
`f=mg`
`f_(max)=muN=mu momega^(2)R`
`f_(max)gef`
`implies mum= momega^(2) R gemg`
`omegagesqrt(g)/(muR)`
`implies omega_(min)=sqrt(g)/(muR)`