5 In an experiment, two balls are set to move on two smooth tracks as shown in the figure below. When ball A leaves the upper track, it is vertically above ball B and both balls are moving at the same horizontal velocity of 2 m s'. Ball A undergoes projectile motion after leaving the track. 2 ms 50 cm B 2ms (a) At the beginning of the experiment, the two balls are simultaneously released from rest at the ends of the two tracks. The following figure shows the initial position of ball A. Find the height h. (b) Consider the time period after ball A leaves the upper track. (2 marks) (i) In the space below, draw the free-body diagrams for balls A and B. (2 marks) (ii) From Newton's laws of motion, explain why the two balls will collide. (3 marks)