15. A volleyball player who weighs 650 Newtons jumps 0.500 meters vertically off the floor. What is her kinetic energy just before hitting the floor?

Kinetic energy just before hitting the floor is 324.57 J

Explanation:

Weight of volleyball player = 650 N

That is

Mass x Acceleration due to gravity = 650

Mass x 9.81 = 650

Mass = 66.26 kg

We also have equation of motion v² = u² + 2as

Initial velocity, u = 0 m/s

Acceleration, a = 9.81 m/s²

Final velocity, v = ?

Displacement, s = 0.5 m

Substituting

v² = u² + 2as

v² = 0² + 2 x 9.81 x 0.5

v = 3.13 m/s

Velocity with which he lands on ground is 3.13 m/s

We have kinetic energy = 0.5 x Mass x Velocity²

Substituting

Kinetic energy = 0.5 x 66.26 x 3.13²

Kinetic energy = 324.57 J

Kinetic energy just before hitting the floor is 324.57 J