Question

when is the kinetic energy maximum for a projectile?

Answer 1

0

Answer 2

When it reaches the ground

Answer 3

Both of the above answers are correct, given no air resistance. If you shoot something in a parabolic arc, it will have its maximum upward velocity at t=0 (right when you launch it) and its maximum downward velocity when it hits the ground. Because gravity is pulling it down at 9.8m/s/s, it will have a velocity of 0 (neither moving up nor down) at the top of the parabola, and will fall back to earth reaching the same speed when it reaches the same level as it started. If you shot something up and off of a cliff, it would reach higher and higher speeds beyond this until it hit the ground.

Answer 4

just at the time of collision with earth