The ball with mass of M = 1kg rolls down from point a at the upper end of 1 / 4 smooth circular arc groove with radius r of 1, and leaves the circular arc horizontally at point B at the height h = 3M above the ground (1) The velocity VA when leaving the circular groove (2) Landing speed VC size (3) The work done by gravity throughout the process

The ball with mass of M = 1kg rolls down from point a at the upper end of 1 / 4 smooth circular arc groove with radius r of 1, and leaves the circular arc horizontally at point B at the height h = 3M above the ground (1) The velocity VA when leaving the circular groove (2) Landing speed VC size (3) The work done by gravity throughout the process

The first and second questions can be solved by the kinetic energy theorem or the law of conservation of mechanical energy. The work done by gravity is only related to the initial and final position. (1) according to the kinetic energy theorem, we get: Mgr = 1 / 2MVA ^ 2 solution: VA = root 2g (2) let the height of the top of the circular arc from the ground be H. then H = 4