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2 years ago

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

re hitting the floor?

1 answer:

allochka39001 [22]2 years ago

3 0

<h2>Kinetic energy just before hitting the floor is 324.57 J</h2>

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

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