The work-energy theorem is applied to the (frictionless) flight of a projectile (launched from ground level). The following statements are correct except
A) the work done by gravity on the projectile from launch point to highest rise is zero.
B) the direction of the velocity at the highest point is horizontal.
C) the final kinetic energy at impact is equal to the initial kinetic energy at launch.
D) the final speed at impact is equal to the initial speed at launch.

Question

Quizplus · Accepted Answer

The work done by gravity on a projectile during its flight is not zero; it converts the projectile's kinetic energy into potential energy until it reaches the highest point, and then back into kinetic energy as it falls back down.

The Work-Energy Theorem Is Applied to the (Frictionless) Flight of a Projectile