A 74.4 kg man steps off a platform 3.04 m above the ground. He keeps his legs st

Question

A 74.4 kg man steps off a platform 3.04 m above the ground. He keeps his legs straight as he falls, but at the moment his feet touch the ground his knees begin to bend, and, treated as a particle, he moves an additional 0.650 m before coming to rest.

Treating him as a particle, what is the magnitude of his acceleration as he slows down if the acceleration is constant? (this is part B)

Use Newton's laws and the results of part B to calculate the force the ground exerts on him while he is slowing down. Express this force in newtons.? (this is part E)

Use Newton's laws and the results of part to calculate the force the ground exerts on him while he is slowing down. Express this force as a multiple of the man's weight.?

What is the magnitude of the reaction force to the force you found in part E?

What is the direction of the reaction force to the force you found in part E?
Upward or downward

Explanation / Answer

3.04*9.81*2=0.650*2*a
a=45.88061m/s2

74.4*(a+9.81)=F
F= 4143.3817 N

m*(a+9.81)=F
F= m*55.69061 N

The same action reaction one of newtons laws

downward, force of ground is upward so he exerts a force downwards

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