physics question

Question

A roller-coaster car has a mass of 494 kg when fully loaded with passengers.

(a) If the vehicle has a speed of 20.7 m/s at point A, what is the force in Newtons exerted by the track on the car at this point?

(b) What is the maximum speed in m/s the vehicle can have at B and still remain on the track?

Answer 1

To solve the problem we need one more data- radius R.

The question related to normal force  N (reaction force) that will be different for different point of the raller coaster. If point A is the upper point of trajectory, then N=mg+F_centr=mg+mv²/R. Thus, to solve the problem we need one more data- radius R.