A block of mass $m_1$ rests on top of mass $m_2$ which sits on a smooth floor. Coefficient of friction between blocks is $\mu$. Find maximum horizontal force applied to $m_2$ so both blocks move together without slipping.
2.
A bead of mass $m$ slides on a smooth wire bent into a vertical circle of radius $R$ rotating about vertical diameter with angular velocity $\omega$. Find equilibrium angle $\theta$.
