How Does Particle Velocity Change in Different Reference Frames?

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The discussion focuses on calculating the velocity of a particle in different reference frames using Galilean and Lorentz transformations. Participants clarify the equations needed for calculations, specifically addressing the definition of beta as a velocity relative to the speed of light. The conversation confirms that when the particle's speed is +0.0c, the transformed velocity simplifies to the observer's velocity. Additionally, there is agreement on how to graph the results, with beta on the horizontal axis and the velocities on the vertical axis. The thread emphasizes the importance of understanding these transformations in the context of special relativity.
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Homework Statement



A particle moves at speed u_{x}= +0.0c according to an observer in the frame S.

a)Calculate the velocity of the particle, u_{x}'_{Gal} and u_{x}'_{SR} as measured by an observer in S'. Let \beta range from -0.95c to +0.95c in increments of 0.05. Put your results in a table.

b)Graph u_{x}'_{Gal} and u_{x}'_{SR} as a function of \beta.

c) Repeat steps a and b for particles with u_{x}=+0.5c, u_{x}=+0.8c, u_{x}=+0.99c and u_{x}=+0.9999c.

*Note* u_{x}'_{Gal} and u_{x}'_{SR} mean the velocities with the Galilean and the lorentz trans., respectfully.

Homework Equations



u'=\frac{u+v}{1+\frac{(u)(v)}{c^{2}}}

The Attempt at a Solution



These are kind of dumb questions but here goes:

First of all the equation with beta in it looks like:

u'=\frac{u+v}{1+\frac{(u)(\beta)}{c}}

Right?

Secondly, when ux=+0.0c the equation just reduces to u'x=v correct?

Thirdly, when it says graph u'Gal and u'SR as functions of beta that means beta on the horizonal and the velocities on the vertical right?
 
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CINA said:

Homework Statement



A particle moves at speed u_{x}= +0.0c according to an observer in the frame S.

a)Calculate the velocity of the particle, u_{x}'_{Gal} and u_{x}'_{SR} as measured by an observer in S'. Let \beta range from -0.95c to +0.95c in increments of 0.05. Put your results in a table.

b)Graph u_{x}'_{Gal} and u_{x}'_{SR} as a function of \beta.

c) Repeat steps a and b for particles with u_{x}=+0.5c, u_{x}=+0.8c, u_{x}=+0.99c and u_{x}=+0.9999c.

*Note* u_{x}'_{Gal} and u_{x}'_{SR} mean the velocities with the Galilean and the lorentz trans., respectfully.

Homework Equations



u'=\frac{u+v}{1+\frac{(u)(v)}{c^{2}}}

The Attempt at a Solution



These are kind of dumb questions but here goes:

First of all the equation with beta in it looks like:

u'=\frac{u+v}{1+\frac{(u)(\beta)}{c}}

Right?
First, what is β defined as? The velocity of what relative to what? Second, in the problem statement you gave, β is proportional to c, so it's a regular velocity. Usually β denotes a velocity as a fraction of the speed of light, i.e. β=0.5 not β=0.5c. If you're using this convention, then yes, what you wrote above is correct because one of the factors of c in the formula was pulled into β.

Secondly, when ux=+0.0c the equation just reduces to u'x=v correct?
Yes.

Thirdly, when it says graph u'Gal and u'SR as functions of beta that means beta on the horizonal and the velocities on the vertical right?
Yes.
 
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