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

I have correctly figured out part a but am stuck on part b. Thanks for your help in advance.

An unstable particle called the pion has a mean lifetime of 25 ns in its own rest frame. A beam of pions travels through the laboratory at a speed of 0.587c.

(a) What is the mean lifetime of the pions as measured in the laboratory frame?

30.75 ns

(b) How far does a pion travel (as measured by laboratory observers) during this time?

m

2. Relevant equations

[ Delta t x c (speed of light) ] / 2

3. The attempt at a solution

using the answer from part a and converting to meters:

[(3.075E-8)(3E8)] / 2 = 4.6125 I've checked for errors and always come up with this number--which according to the web program is incorrect.

What am I not doing/understanding?

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# Homework Help: Special relativity question

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