A particle slides down a frictionless parabolic track starting from rest at point A (Fig. 4.2). Point B is at the vertex of parabola and point C is at a height less than that of point A. After C, the particle moves freely in air as a projectile. If the particle reaches highest point at P, then
(a) KE at P = KE at B
(b) height at P = height at A
(c) total energy at P = total energy at A
(d) time of travel from A to B = time of travel from B to P.
The answer is the option (c)
Explanation: total energy at a point in the path remains the same as there is no friction between air and plane on paths A, B and C
As we know through the energy conservation law, total energy at point P will be same as total energy at point A.
Hence, option c is correct.