From Chris' perspective Bob is travelling with 1.5*10(adsbygoogle = window.adsbygoogle || []).push({}); ^{8}m/s in direction a. Angelica is also travelling with 2.4*10^{8}m/s in direction a.

From Bob's perspective Chris is travelling with 1.5*10^{8}m/s in direction b (The opposite of x). Angelica is travelling with 1.5*10^{8}m/s in direction a.

They all have a mass of 1

I am pretty sure these numbers are right. I used w = (u+v)/(1+(u*v)/(c^{2})) To calculate the relative speeds.

I used the calculation in the picture to calculate the E_{k}of Bob. I also calculated the E_{k}of Angelica, all from chris' perspective. Now the outcome that I was expecting was that Bob's E_{k}would be half of Angelica's E_{k}when looking from Chris' perspective. Because Angelica is also travelling with 1.5*10^{8}m/s when measured from Bob's perspective. Why does this not count up?

I am sorry if a skipped a few vital steps. All of my special relativity knowledge comes from self-studying. We don't get this in school.

Thank you in advance.

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# I Speed and kinetic energy in different inertial frames.

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