Is 2D Conservation of Momentum Possible? A Visual Analysis

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SUMMARY

The discussion centers on the conservation of momentum in a 2D system, highlighting the challenges in identifying angles where both horizontal and vertical components remain conserved. Participants express skepticism regarding the exercise's validity, questioning the assumptions about kinetic energy conservation and the role of the center of mass (COM). A user named @Orodruin provided insights that helped clarify the confusion, leading to a revised understanding of the problem, although issues with missing units in calculations were noted.

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  • Understanding of linear momentum in physics
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  • Knowledge of kinetic energy conservation principles
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Students and educators in physics, particularly those focusing on mechanics, as well as anyone interested in understanding the complexities of momentum conservation in two-dimensional systems.

Saptarshi Sarkar
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Homework Statement
A high-velocity missile, travelling in a horizontal line with a kinetic energy of 3.0 Giga-Joules (GJ), explodes in flight and breaks into two pieces A and B of equal mass. One of these pieces (A) flies off in
a straight line perpendicular to the original direction in which the missile was moving and its kinetic energy is found to be 2.0 GJ. If gravity can be neglected for such high-velocity projectiles, it follows
that the other piece (B) flew off in a direction at an angle with the original direction of
Relevant Equations
##p = \sqrt {2mK.E.}##
I am unable to find any angle for which the horizontal and vertical components of the linear momentum are conserved.

I have added an image of my attempt
 

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Conclusion ? The exercise composer is attempting to trick you ?
 
  • Skeptical
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BvU said:
Conclusion ? The exercise composer is attempting to trick you ?

Maybe! The question itself seems weird. The COM of the system can no way stay in the same path, but it must.
 
What makes you think kinetic energy is conserved?
 
  • Informative
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Where did the ##10^9## come from:
1578011959881.png


Edit: Oops, I see that @Orodruin beat me to the punch!
 
  • Wow
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Thanks a lot for the help! I had a second attempt at the question and this the answer I arrived at.
 

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Looks fine apart from all the missing units.
 
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Instead of numbers and units you could simply use ##E_0## and ##\frac 2 3 E_0## for the given energy.
 
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