(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A chain of length L and total mass M is released from rest with its lower end just touching the top of a table. Find the force exerted by the table on the chain after the chain has fallen through a distance x. (Assume each link comes to rest the instant it reaches the table.)

2. Relevant equations

p= mv

ek= (1/2)mv^2

3. The attempt at a solution

First, I tried to find the force by taking the derivative of kinetic energy:

ek= (1/2)mv^2

m= M(L-x)/L, v^2= 2xg

ek= Mxg(L-x)/L

d/dt(ek)= Mgv-2Mgxv/L

F= [d/dt(ek)]/v= Mg-2Mgx/L

But this turns out to be the wrong answer. Any advice? Thanks.

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

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Momentum Problem on a chain

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