Answer:
[tex]\omega = \sqrt{\frac{4g}{3R}}[/tex]
Explanation:
By conservation of energy:
The initial energy of the system is: [tex]M*g*R[/tex]
The final energy of the system is: [tex]1/2*M*R^2*\omega^2+1/2*(1/2*M*R^2)*\omega^2[/tex]
[tex]M*g*R=1/2*M*R^2*\omega^2+1/2*(1/2*M*R^2)*\omega^2[/tex]
Solving for ω:
[tex]\omega=\sqrt{\frac{4g}{3R}}[/tex]