How Fast is the Missile Relative to the Rocket?

AI Thread Summary
The discussion focuses on a physics problem involving a rocket traveling at 0.8c that fires a missile at 0.6c towards a planet 2 light years away. The main questions are how long it takes for the missile to reach the planet and the relative speed of the missile to the rocket. The initial responses confirm the approach and solution are correct. The calculations involve understanding relativistic speeds and distances. The thread concludes with affirmation of the user's solution.
henrco
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Hi,
Could i please get advice on this problem and confirm that my approach and solution are correct?
Thanks in advance.

1. Homework Statement
An enemy space rocket traveling at speed 0.8c towards the planet Zog fires a missile in the direction parallel to its own path. Relative to the rocket, the missile travels at v = 0.6c.

a)How long will the missile take to reach Zog if it is 2 light years distant (in the rest frame of the planet) at the
time of firing?

b) Find the relative speed of the missile to the rocket:

Homework Equations


upload_2016-3-17_14-35-1.png


The Attempt at a Solution



upload_2016-3-17_14-36-44.png
[/B]
 
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Looks good to me.
 
  • Like
Likes henrco
Excellent, thank you.
 
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