How Fast is the Alien Spacecraft Flying Overhead?

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Homework Help Overview

The discussion revolves around a physics problem involving the speed of an alien spacecraft based on the observed duration of a signal light. The problem touches on concepts of relativity and the implications of measuring time from different reference frames.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to calculate the speed of the spacecraft but arrives at a result exceeding the speed of light, prompting questions about potential miscalculations or misunderstandings of the problem. Other participants suggest showing work to identify errors and provide feedback.

Discussion Status

The discussion has seen some participants offering guidance on how to approach the problem, with one indicating a resolution to their miscalculation. However, there remains a lack of consensus on the correct interpretation of the results and the underlying physics.

Contextual Notes

There is an indication of confusion regarding the relativistic effects on time measurement between different observers, which may be influencing the calculations and interpretations presented.

da_warped_1
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hey i just need a lil help with this question

An alien spacecraft is flying overhead at a great distance as you stand in your backyard. Yyou see a bright signal light in the spaceship blink on for 190.0 ms. The commander of the spacecraft measures that the signal is on for 12.0 ms.

what is the speed of the spacecraft relative to the earth?

i calculated the speed and it comes out to be greater than the speed of light, which is impossible. just wondering if i had calculated it wrong or maybe someone has a better explanation!

thanks
 
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Show your work and someone will probably be able to tell you where you went wrong. Otherwise we can only guess!
 
i worked it out, just a simple miscalculation.

cheers
 
you should get ...

v=0.998c​

So that's a fast vessel.

pess
 

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