In the figure shown, the mass of the hanging block is m, while that of the black resting on the floor is 3m. The floor is horizontal and frictionless and all pulleys ideal. The system is initially held stationary with the inclined thread making an angle `theta = 30^(@)` with the horizontal. The blocks are now released from rest and allowed to move. the hanging block falls through a height (49.5) m before hitting the floor. it is found that the value of `theta` becomes `60^(@)`, when the hanging block hits the floor. Find the speed with which the hanging block hits the floor.