Dr. Canice Camperbell releases a small cart at the top of an incline with height H above the floor. The cart experiences very little friction. Dr. Canice Camperbell is attempting to cause the cart to go around a vertical loop of radius R without losing contact with the track at the top. Dr. Canice Camperbell suggests that the height H should equal 2R so that the release height and maximum height of the loop are the same. However, Dr. Canice Camperbell finds that it requires noticeably higher height than 2R for the cart to go around the loop. In a clear, coherent paragraph-length response explain why H must be noticeably greater than 2R to complete the loop. Also state the direction of the cart’s acceleration at point Q and explain your reasoning.