Which one of the following best explains why the time taken by a projectile to rise…
PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
Which one of the following best explains why the time taken by a projectile to rise to its maximum height equals the time taken to fall back to the point of projection (air resistance neglected)?
(a) The vertical component of acceleration becomes zero at the highest point, so the ascent stops and the descent begins.
(b) The vertical acceleration remains constant (downward), reversing the vertical velocity symmetrically about zero.
(c) Because mechanical energy is conserved, the loss of kinetic energy on the way up equals the gain on the way down, making the time intervals equal.
(d) The horizontal component of velocity stays constant throughout the motion, forcing equal upward and downward times.