Riding a Loop-theLoop. A car in an amusement park ride rolls without friction around a track (Fig. P7.42). The car starts from rest at point A at a height h above the bottom of the loop. Treat the car as a particle. (a) What is the minimum value of h (in terms of R) such that the car moves around the loop without falling off at the top (point B)? (b) If h = 3.50R and R = 14.0 m, compute the speed, radial acceleration, and tangential acceleration of the passengers when the car is at point C, whic