Calculating Speed, Acceleration & Force of a 75kg Man Falling 3.10m

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A 75 kg man falls 3.10 meters, reaching a speed of approximately 7.79 m/s upon impact with the ground. To determine his deceleration as he slows down, the average force exerted on the ground can be calculated using the equation of motion, considering the additional 0.6 meters he moves while bending his knees. The net force acting on the man during the fall can be derived from his weight and the deceleration experienced upon impact. The discussion emphasizes breaking the problem into two parts for accurate calculations. Understanding these principles is crucial for analyzing motion and forces in free fall scenarios.
alafleur1
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1) A 75 kg man falls 3.10 meters to the ground. He moves an additional 0.6 meters as his knees bend when he hits the ground.
a) what is his speed as his speed when his feet touch the ground? - I solved this as 7.79487 m/s
b) What is his acceleration as he slows down if acceleration is assumed to be a constant? How do i get this?
c) What is the net force on the man and what is the average force his feet exert on the ground as he slows?
 
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Hint: use the basic equation of motion:

x = v_0t + \frac{1}{2} at^2

and think of it as two separate problems.
 
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