Problem 1.68

At the moment $t=0$ the force $F=a t$ is applied to a small body of mass $m$ resting on a smooth horizontal plane $(a$ is a constant $)$ The permanent direction of this force forms an angle $\alpha$ with the horizontal (Fig. 1.14). Find: (a) the velocity of the body at the moment of its breaking off the plane; (b) the distance traversed by the body up to this moment.