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

A ship is moving at 0.45c with respect to earth, and a beacon is fired perpendicular to the ship at 0.65c with respect to the ship. Find the velocity of the beacon with respect to earth.

2. Relevant equations

3. The attempt at a solution

My main problem here is seeing which numbers go where in the equations. My book basically just shows them, then has an example of adding velocities in one dimension >_>.

From what I gather, u_{x}and u_{y}are the components of the velocity of the beacon with respect to earth. u'_{x}and u'_{y}are the components of the velocity in the ship's frame, making u'_{x}= 0 and u'_{y}= 0.65c

This however makes the v's in the denominator cancel out, and I get u_{x}= v and u_{y}= 0.65[tex]\sqrt{1/ (v^{2}/c^{2}})[/tex]

Plugging in my value of u_{x}for v I get u_{y}= 0.65[tex]\sqrt{1/ (u_{x}^{2}/c^{2}})[/tex] which doesn't lead me anywhere.

Its pretty clear that I'm doing something wrong, I just ned a nudge in the right direction. Here's my picture of the problem (not to scale =P)

http://www.geocities.com/zombierobopirate/relativity.png

Thanks in advance

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

Dismiss Notice

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: Having trouble connecting Lorentz transformations with my problem

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