일반물리학 1 — Force and Motion-II: Problem 48

48 A roller-coaster car has a mass of 1300 kg when fully loaded with passengers. As the car passes over the top of a circular hill of radius 20 m, its speed is not changing. At the top of the hill, what are the (a) magnitude \(F_N\) and (b) direction (up or down) of the normal force on the car from the track if the car’s speed is \(v = 11 \text{ m/s}\)? What are (c) \(F_N\) and (d) the direction if \(v = 14 \text{ m/s}\)?