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1. The problem statement, all variables and given/known data

Im trying to calculate the force encountered by an object falling due to gravity that is caught by a rope.

Obviously F=ma and since mass is constant I need to find the rate of deceleration. I've tried to using the equation v^2 = u^2 +2ax as v = 0 and u =1.57 m/s so I need to find x to calculate the deceleration.

In order to calculate s I was going to use the equation for young's modulus which is σ/ε and calculate the strain, As E = 200 GPa and I just need to find the stress on the rope, but here in lies my problem, as I can not figure out how to do this. I know the CSA as r = 0.003 m but I don't know what to use for my force value as surely the force is what I am trying to work out in the first place, and I don't think using mass * gravity is sufficient as the force must be greater as we have a velocity

2. Relevant equations

F = m*a

v^2 = u^2 + 2ax

x = l*σ/E

σ =F/A

3. The attempt at a solution

My attempt is described above but I just can't figure out what to use for F

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# Homework Help: Deceleration of a falling load of a rope

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