Center of mass / momentum chain

AI Thread Summary
The discussion revolves around calculating the acceleration of a flexible chain falling from a frictionless table, with specific parameters provided. Initially, it was thought that the acceleration would simply equal the acceleration due to gravity (9.8 m/s²), but further analysis revealed that the effective hanging mass must be considered to determine the actual acceleration. The user successfully calculated the hanging mass when 3.6 m of the chain is vertical, leading to the correct acceleration value. The conversation then shifts to finding the velocity of the chain at that point, with participants seeking guidance on how to approach this varying acceleration scenario. Overall, the thread highlights the importance of understanding forces acting on the system to solve the problem accurately.
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Homework Statement


Given: A uniform flexible chain whose mass
is 4.1 kg and length is 5 m. A table whose top
is frictionless.
Initially you are holding the chain at rest
and one-half of the length of the chain is hung
over the edge of the table. When you let loose
of the chain it falls downward.
The acceleration of gravity is 9.8 m/s2
Find the acceleration a of the chain when
the length of the chain hanging vertically is
3.6 m: Answer in units of m/s2.

Homework Equations


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The Attempt at a Solution


Well I am not exactly sure to figure this out, but it seems as if it would be extremely easy to do seeing as how the acceleration due to gravity is 9.8. Unfortunatly this is wrong but I have yet to figure out what other force would be giving it an acceleration other than 9.8
 
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Any help would be much appreciated.
 
Alrighty well thank you very much for helping. The second part of the question is asking for the velocity at that point. Rather than an answer could anyone help me with what to start with for this point seeing as how the acceleration is varying. Thanks.
 
Sorry, I think I was wrong. I'm not entirely sure why the acceleration isn't just g. If nothing else it should be constant
 
Actually you were right lol. I calculated the hanging mass when there is that much of the chain hanging. I got 2.9252kg the divided that by the entire mass and came out with the correct answer for the acceleration. Now all I need is how to find the velocity at that point.
 

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