Do A and C have same or different KE at the end?

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In a frictionless ramp scenario, the conservation of energy principle indicates that both blocks A and C should have the same final kinetic energy (KE) since their initial potential energy (PE) is equal (mgh). Despite C traveling a shorter horizontal distance, the lack of energy losses confirms that their final KE remains the same. The discussion highlights confusion over a template that suggests different rankings for A and C, but ultimately, it is clarified that their order does not affect the outcome. Participants agree that the final KE for both blocks can be considered identical. The conclusion emphasizes that the ranking of A and C can be interchangeable without impacting the results.
JessicaHelena
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Homework Statement



Please look at the attached screenshot.

Homework Equations



Assuming the ramp is frictionless, Ei = Ef and thus mgh = KE ( = 1/2mv^2, which isn't really necessary here)

The Attempt at a Solution


I'm okay with all other examples except for A and C. From the answer template given, I don't think I'm allowed to let two different blocks have the same final KE, but even though C travels a shorter horizontal distance, the conservation of energy tells me they should have the same KE at the end (bc their mgh is the same)! Am I missing something here?
 

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You are correct and the answer template is a bit misleading. Conclusion: A and C can be entered in the order of your choice. Or in one box if the work is judged by a human instead of a counting machine.
 
JessicaHelena said:
I'm okay with all other examples except for A and C. From the answer template given, I don't think I'm allowed to let two different blocks have the same final KE, but even though C travels a shorter horizontal distance, the conservation of energy tells me they should have the same KE at the end (bc their mgh is the same)! Am I missing something here?

I don't think so - since there are no losses - the final KE should be same as initial PE - mgh as you indicated. I guess in the template it wouldn't matter if you rank AC or CA in either order.
 
Alright, I'll put it that way then. Thank you!
 

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