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AbigailM
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Preparing for a classical prelim by going over previous exams.
A relativistic meter stick moves with speed v in the lab. It collides head on with an impenetrable wall completely inelastically, thereby coming to rest in the lab frame. What is the maximum length of the stick in the lab after the collision?
[itex]p=\gamma mv[/itex]
[itex]L_{0}=\gamma L[/itex]
[itex]E^{2}=(pc)^{2}+(mc^{2})^{2}[/itex]
Since the particle comes to rest after hitting the wall, I've assumed that the wall is infinitely massive. :\ not sure if that is a good idea.
[itex]E_{0}=E_{1}[/itex]
[itex](p_{0}c)^{2}+(m_{0}c^{2})^{2}=(m_{0}c^{2})^{2}+(m_{wall}c^{2})^{2}[/itex]
[itex]p=\gamma m_{0}v_{0}=\infty[/itex]
[itex]\gamma=\frac{L_{0}}{L}[/itex]
[itex]\frac{L_{0}}{L}m_{0}v_{0}=\infty[/itex]
[itex]L_{0}=\infty[/itex]
Not sure if this is correct at all. Any hints or ideas?
Thanks.
Homework Statement
A relativistic meter stick moves with speed v in the lab. It collides head on with an impenetrable wall completely inelastically, thereby coming to rest in the lab frame. What is the maximum length of the stick in the lab after the collision?
Homework Equations
[itex]p=\gamma mv[/itex]
[itex]L_{0}=\gamma L[/itex]
[itex]E^{2}=(pc)^{2}+(mc^{2})^{2}[/itex]
The Attempt at a Solution
Since the particle comes to rest after hitting the wall, I've assumed that the wall is infinitely massive. :\ not sure if that is a good idea.
[itex]E_{0}=E_{1}[/itex]
[itex](p_{0}c)^{2}+(m_{0}c^{2})^{2}=(m_{0}c^{2})^{2}+(m_{wall}c^{2})^{2}[/itex]
[itex]p=\gamma m_{0}v_{0}=\infty[/itex]
[itex]\gamma=\frac{L_{0}}{L}[/itex]
[itex]\frac{L_{0}}{L}m_{0}v_{0}=\infty[/itex]
[itex]L_{0}=\infty[/itex]
Not sure if this is correct at all. Any hints or ideas?
Thanks.