Observe the golfer ball shown in the image. (time, t=7.50 s time from when the ball is hit to the max height.)

If this is the time for the ball to reach its max height, what is the total hang time (from the time the ball is hit to the max height to when the ball hits the ground). (Assume no air resistance or spin.)

If the time to reach max height is 7.5 s then the time to fall to the ground would be 7.5 s and the total time of flight would be 15 s.

Vy / g = tup      Vy is initial vertical speed

Vf / g = tdown   Vf is the final vertical speed

Speed (vertical) at end of trajectory must the the same as the speed at the start of the trajectory for energy to be conserved.