(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

On a spaceship moving 5/6C, an astronaut fires a light pulse from a gun. The barrel of the gun makes an angle of 60 degrees from the X direction relative to the spaceship. What angle does the gun make in the rest frame of an observer on Earth and what angle does the light pulse move for the same Earth observer?

2. Relevant equations

[tex]u^{'}_{x}[/tex]=C*cos[tex]\theta[/tex]

[tex]V^{'}_{x}[/tex]=5/6C

[tex]u_{x}[/tex]=[tex]\stackrel{u^{'}_{x}+V^{'}_{x}}{1+\stackrel{u^{'}_{x}V^{'}_{x}}{c^{2}}}[/tex]

For some reason the formatting didn't work out - the last equation is Einstein's Relative Addition formula.

3. The attempt at a solution

I found a value of 2.8216x[tex]10^{8}[/tex] for the relative velocity in the x direction of the light pulse to the Earth observer, but I do not know what the next step would be. I suspect that the angle of the gun itself does not change, but I'm not sure how to prove or disprove this. Thanks!

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Relativity: Projectile Motion at an Angle on Spaceship

**Physics Forums | Science Articles, Homework Help, Discussion**