Shelly rolls ball a in the positive x direction with a velocity of 7.5 meters/second. it hits stationary ball b and they undergo elastic collision. the two balls have different masses. which of the following statements is true?

A55-kg pilot flies a jet trainer in a half vertical loop of 1200-m radius so that the speed of the trainer decreases at a constant rate. knowing that the plane has a speed of 550 km/h at point a, and the pilot experiences weightlessness at point c (i. e., the normal force from the seat bottom is zero), determine (a) the deceleration of the plane, (b) the force exerted on her by the seat of the trainer when the trainer is at point b.