Calculating Frequency of Star's Radio Signals from Earth

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A star moving at 0.8c sends radio signals to Earth once every second according to its time scale. Due to time dilation, the signals are received every 2.24 seconds on Earth, resulting in a frequency of 0.45 signals per second. The calculation uses the formula Δts = Δtm/√(1 – (v^2/c^2)). A participant raises a concern about whether the increasing distance of the star affects the signal reception frequency. Overall, the discussion focuses on the implications of relativistic effects on signal timing.
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Homework Statement



A distant star has been measured as moving at a speed of 0.8c away from Earth. If a planet of this star sends radio signals to Earth once every second (according to their time scale), how often would we receive them (according to out time scale)?

Homework Equations



Δts = Δtm/ √(1 – (v^2/c^2)

The Attempt at a Solution



Δts = Δtm/ √(1 – (0.8c)^2/c^2)
= 1/ √(1 – (0.8c)^2/c^2)
= 2.24 s

f = 1/2.24 s
= .45 signal/second

Therefore, we would receive .45 signal/second

*does this look ok?
 
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hi crosbykins! :smile:

have you taken account of the fact that the distance each signal has to travel is increasing?
 
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