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

A [tex]\pi[/tex]+ meson whose rest energy is 140 MeV is created 100km above sea level in the earth's atmosphere. The pi+ meson has a total energy of 1.5X10^5 MeV and is moving vertically downward. If it disintegrates 2x10^-8 s after it's creation as determined in its own frame of reference, at what altitude above sea level does the disintegration occur?

2. Relevant equations

energy conservation.

3. The attempt at a solution

I used energy const. to get the velocity of the particle, then attempted to calculate it's displacement which is approximately 6 km and I get approx. 94 km.

the correct answer is given to be 93.6, which is not a small error in my opinion.

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# Homework Help: Mass, energy problem in relativity

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