Force Problem: Calculating Ground Force on Jumping Boy with Stiff-Legged Landing

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A boy weighing 400 N jumps from a height of 2.00 m, landing stiff-legged with a ground compression of 2.00 cm. The force of the ground on his feet is calculated to be 40,400 N, assuming negligible compression of tissue and bones. The solution involves using the formula F = (weight/acceleration due to gravity) * gravity + weight. The discussion also briefly touches on the concept of work and energy, specifically Wnc = ΔE, but this was ultimately set aside. The calculation confirms the significant ground force experienced during the landing.
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A boy weighing 4.00 *10^2 N jumps from a height of
2.00 m to the ground below. Assume that the force of the
ground on his feet is constant.
Compute the force of the ground on his feet if he
jumps stiff-legged, the ground compresses 2.00 cm,
and the compression of tissue and bones is negligible

solution:

F = (4.00*10^2/9.8)(9.8) + (4.00*10^2) = 800
answer is 4.04 *10^4 N
 
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Could I use the formula

Wnc = ΔE ?
 
Nevermind I got it
 
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