A rectangular block of mass \( M \) and height \( a \) is resting on a smooth level surface. A f...

A rectangular block of mass \( M \) and height \( a \) is resting on a smooth level surface. A force \( F \) is applied to one corner as shown in figure. At what point should a parallel force \( 3 F \) be applied in order that the block motion? Assume normal shall undergo pure translational montact force between the block and surface passes through the centre of gravity of the block.
(1) \( \frac{a}{3} \) vertically above centre of gravity
(2) \( \frac{a}{6} \) vertically above centre of gravity
(3) No such point exists
(4) it is not possible