Is 2D Conservation of Momentum Possible? A Visual Analysis

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Homework Help Overview

The discussion revolves around the conservation of momentum in a two-dimensional context, with participants analyzing the implications of a visual representation related to the problem. The original poster expresses difficulty in identifying angles that would allow for the conservation of both horizontal and vertical components of linear momentum.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants are questioning the assumptions behind the conservation of momentum, particularly in relation to the center of mass and the potential trickiness of the exercise. There are inquiries about the conservation of kinetic energy and the origins of specific numerical values mentioned in the discussion.

Discussion Status

The discussion is active, with participants sharing their thoughts and interpretations. Some have attempted to rework the problem, while others are pointing out potential oversights, such as missing units in calculations. There is no explicit consensus on the interpretations being explored.

Contextual Notes

Participants are navigating the complexities of the problem, including the implications of energy conservation and the specifics of the exercise's setup. There are indications of confusion regarding the parameters and assumptions involved in the analysis.

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
 

Attachments

  • IMG_20200103_052558.jpg
    IMG_20200103_052558.jpg
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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.
 

Attachments

  • IMG_20200103_193233.jpg
    IMG_20200103_193233.jpg
    61.7 KB · Views: 334
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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