# Particle Physics - Muon questionWatch

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#1
Really struggling with this question, not sure where to go with it:

1.) Cosmic-ray reactions that create muons take place between 15 000m and 40 000m above sea level.
a.) How long would it take a particle moving at the speed of light to cover this distance?
b.) Compare this number with the muon lifetime. How is it that so many muons can reach the surface of the Earth?

So the time it takes to reach Earth is longer than the muon lifetime (2.19703x10^-6) but I can't think of any way to give a simple answer to this without getting really in depth? Maybe relativity or Lorentz transforms. Not really sure so any help would be appreciated
0
2 years ago
#2
(Original post by zenda)
Really struggling with this question, not sure where to go with it:

1.) Cosmic-ray reactions that create muons take place between 15 000m and 40 000m above sea level.
a.) How long would it take a particle moving at the speed of light to cover this distance?
b.) Compare this number with the muon lifetime. How is it that so many muons can reach the surface of the Earth?

So the time it takes to reach Earth is longer than the muon lifetime (2.19703x10^-6) but I can't think of any way to give a simple answer to this without getting really in depth? Maybe relativity or Lorentz transforms. Not really sure so any help would be appreciated
You have to use special relativity.
0
#3
(Original post by alow)
You have to use special relativity.
Thank you, I thought that was the way I was going but just kind of needed someone to confirm my suspicions. Thanks
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