2 objects travelling in separate dimensions

[nSMITH]

Homework Statement

One object is traveling in the x direction at 0.935c and another is traveling at 0.98c in the z direction. Determine the overall velocity of the second object from the point of view of the first object.

Homework Equations

v'x=(vx-v)/(1-vx*(v/c^2))

The Attempt at a Solution

I have no idea where to start

 

[irycio]

Having no idea where to start, you should have checked wikipedia:P
http://en.wikipedia.org/wiki/Velocity-addition_formula
And off you go with a beautiful formula for adding orthogonal velocities in SR. Couple more years and I'll be able to derive it myself \m/. Till then, use google :P

 

[nSMITH]

You think I'd be asking here if I could figure it out from wikipedia/google?

 

[irycio]

My apologies for providing you with a wrong formula.
No apologies, however, for suggesting you to google, because after a couple more minutes... http://www.mathpages.com/home/kmath216/kmath216.htm here you are, the proper formula:
v=Sqrt[1-(1-vx^2)(1-vy^2)]
I'm afraid i don't know where it comes from, but the result seems fine, as it increases both of the velocities, still being less then c, whereas the formula form wikipedia gave the result that was lesser than 0.98c.
No offence :)