Conservation of a mechanical energy question

AI Thread Summary
The discussion centers on a conservation of mechanical energy problem involving two masses in an Atwood machine, where one mass (m2) has an initial upward speed. The goal is to determine how high m2 rises before coming to rest. Key points include setting up the initial mechanical energy of the system, which consists of both kinetic and potential energy, and recognizing that when m2 momentarily stops, the energy is purely potential. It is emphasized that the height increase for m2 must equal the height decrease for the lighter mass (m1) due to the taut string. The solution involves calculating the acceleration of the masses and applying kinematics to find the distance m2 rises.
wilmerena
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Hi, this is my first time here and Id like to thank in advance for any help offered :smile:
Im having trouble with the following question about 2 masses in an atwoods machine.

2 masses are initially at rest at the same height, if m2 has a given initial upward speed, how high does m2 rise above its initial position before momentarily coming to rest, (masses for each are given with m2 being heavier)

I know that I need to show some work before I should post this, but I embarrased to say I don't know how to even apporach it :frown:

any tips will be greatly appreciated :biggrin:
 
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Welcome to PF!
This is a conservation of mechanical energy question.
Set up the initial mechanical energy of the whole system (kinetic+potential)
When the system falls momentarily at rest (assuming that the string remains taut all the time), the system only have potential energy.
As a hint, note that with a taut, inextensible string, the increase of height for m2 must equal the decrease of height for m1
 
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First, find the acceleration of the masses. Then use some kinematics to find the distance. Should be dead easy.
 
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