Two blocks m$4=1\mathrm{.}1$ kg and m$2=7\mathrm{.}5$ kg are connected by a massless rope over a pulley with radius r$=1\mathrm{.}6$ m$.$ If the pulley has a moment ofinertia $=30$ kgm$?.$ Determine the angular acceleration of the pulley caused by the torques associated with the two weights.