AP French Relativity chapter 3 problem

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The discussion centers on solving a problem related to the relativistic Doppler shift in the context of a star's motion. Participants note that the problem may not require relativistic equations since the star's speed is significantly less than the speed of light. Instead, it suggests deriving the velocity function of the star over time and determining when light emitted from the star reaches Earth. The emphasis is on calculating the time of emission based on the star's velocity and the speed of light. Understanding these concepts is crucial for accurately addressing the problem.
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Homework Statement
the question is contained in my attempt at a solution as I can't add images anywhere else
Relevant Equations
I assume we will have to use the relativistic doppler shift in order to find our answer, but that's all I can really gather from how to attempt this
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ka_reem13 said:
Relevant Equations:: I assume we will have to use the relativistic doppler shift in order to find our answer, but that's all I can really gather from how to attempt this
I think French wants you to assume that the speed of light depends on the motion of the source. In which case, you cannot use the relativistic Doppler shift, but have to calculate the shift for yourself.
 
ka_reem13 said:
Relevant Equations:: I assume we will have to use the relativistic doppler shift in order to find our answer, but that's all I can really gather from how to attempt this

This problem does not require any results from relativity. The star's speed is much less than the speed of light. Consider the following:

(1) What is the function ##v_r(t)## that expresses ##v_r## as a function of time ##t## and the orbital period ##T##? For convenience, choose ##t = 0## when the star is farthest from the earth.

(2) Suppose someone on earth at an arbitrary time ##t## observes light from the star. At what earlier time ##t_0## was this light emitted from the star under the assumption that the light travels from the star to earth at speed ##c+v_r(t_0)##? Express ##t_0## in terms of ##t##, ##R##, ##c##, and ##v_r(t_0)##.
 
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