Relating Kinetic Energies and Masses of Two Objects

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The discussion revolves around calculating the ratio of kinetic energies for two objects with masses m1 and m2. The user correctly derived the velocity ratio as v2x/v1x = -m1/m2 but struggles to express the kinetic energy ratio in terms of m1 and m2. They initially concluded that K1/K2 = m2/m1, but faced issues with the homework system marking it incorrect. The professor indicated that the new system may have errors, which could explain the discrepancies in grading. The user is seeking clarification and assistance to resolve the issue with their answer.
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Homework Statement


Two objects of inertias m1 and m2 start from rest and then interact with each other (assume neither is interacting with any other object).
What is the ratio of their kinetic energies at any instant?

Homework Equations


\frac{K_{1}}{K_{2}} = ?
The first part of the equation asked me to relate velocities to masses and I got a correct answer of

\frac{v_{2x}}{v_{1x}} = -\frac{m_{1}}{m_{2}}

The Attempt at a Solution


I know that Kinetic Energy is half of the mass times the square of the velocity, and that's where my attempt falls apart, because I have to express the answer in terms of m1 and m2, but they're already in KE so I don't understand how that works out. My answer I got was

\frac{K_{1}}{K_{2}} = \frac{m_{2}}{m_{1}}

Without the negative cause it is the square of the velocity and that will eliminate any negatives. Please help.
 
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So what is your question?
The answer looks OK.
 
nasu said:
So what is your question?
The answer looks OK.

It's not okay though :( apparently I am not correct :mad:
 
The answer you have obtained is correct .
 
B3NR4Y said:
It's not okay though :( apparently I am not correct :mad:

How do you know this? What do you think is the correct answer?
 
nasu said:
How do you know this? What do you think is the correct answer?

It's part of a homework assignment and when I put in an answer it spits out a correct or incorrect judgement. I put in my answer and it's incorrect. The professor said things like this would happen though, and when they did to come to him because we're using a new system and there are mistakes in it that he's found. I hope that is the case because I tried every combination of subscript and now they most I can get on the question is 50% for a correct answer regardless of the amount of tries.
 
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