`T = Mg`

`T + mu N = m omega^(2)R`
`Mg + muMg = m omega^(2)R`
`omega_(max) =sqrt(((M + mu m) g)/(mR))`
For maximum angular velocity , the direction of friction will be toward radius direction (away from center) Hence.
`omega_(min) =sqrt(((M + mu m) g)/(mR))`