A small block of mass is fired with an initial speed of along a horizontal section of frictionless track as shown in the top portion of the figure. The block then moves along the frictionless, semicircular, vertical tracks of radius . (a) Determine the force exerted by the track on the block at points A and B. (b) The bottom of the track consists of a section () with friction. Determine the coefficient of kinetic friction between the block and that portion of the bottom track if the block just makes it to point C on the first trip.
