In the high jump, the kinetic energy of an athlete is transformed into gravitational potential energy without the aid of a pole. With what minimum speed must the athlete leave the ground in order to lift his center of mass 1.75 m and cross the bar with a speed of 0.63 m/s?

Answer 1

energy at top=mgh+1/2 m vattop^2
energy at bottom:1/2 m vlaunch^2
set them equal, and solve for vlaunch

Answer 2

gfh