Normal reaction provides centripetal force:
\[ N = M \omega^2 R \]
For minimum ω, friction is maximum:
\[ f_{max} = \mu N \]
Equilibrium vertically:
\[ \mu N = Mg \]
\[ \mu (M\omega^2 R) = Mg \]
Cancel M:
\[ \mu \omega^2 R = g \]
\[ \omega^2 = \frac{g}{\mu R} \]
\[ \boxed{\omega = \sqrt{\frac{g}{\mu R}}} \]
Updated for JEE Main 2026: This PYQ is important for JEE Mains, JEE Advanced and other competitive exams. Practice more questions from this chapter.