Mechanical engergy, energy conservation

AI Thread Summary
The discussion revolves around calculating the velocity of a 10-kg block after it passes through a frictional section of a track. The block's initial velocity at point B is determined to be 8.85 m/s, and it loses 88.2 J of energy while traveling between points B and C due to friction. The key equations involve work-energy principles, specifically the relationship between work done and changes in kinetic and potential energy. The participant is attempting to incorporate the mass of a second block into their calculations but is unsure if it should be included for the velocity at point C. Ultimately, understanding the energy loss will help determine the block's velocity after passing through the frictional section.
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Homework Statement


A 10-kg block is released from point A. The track is frictionless except from the portion between B and C which has a length of 3.0 meters. The block travels down the track, passes through BC and first collides with a small block (m=2kg), then they travel together and later hit the spring.

Q: Find the velocity of the block after it passes BC

There were two questions before it, find the velocity of the block when it reaches point B at the bottom of the track and it's 8.85m/s then I found the work between B and C which is -88.2 J. I tried setting up different equations to find the velocity after it passes B and C, but I am missing something.

Homework Equations


Wf=E2-E1
E2=E1
1/2mv^2, mgh, 1/2kx^2, mgx

The Attempt at a Solution


I tried setting the equation equal to the work, -88.2=1/2V^2(m+m), I recently tried -2μkgd=mv2^2-(mv1^2+2mgh1). I am not sure if I am supposed to have the second block in there or not.
 

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For the velocity at point C, the second block does not matter - it is not a part of the motion yet.
You probably have the energy of the first block at point B as intermediate result. If it loses 88.2J, what is its energy at point C? This allows to calculate the velocity.
 
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