A muon is an unstable particle that has an average lifetime of ...

[humphriesbr@me.com]

A muon is an unstable particle that has an average lifetime of 1.52  10-6 s.
 
  This is the time interval between its creation in a nuclear process and its extinction into decay products, as measured in a frame of reference at rest with respect to the muon. An average muon is observed by a scientist on Earth to travel 342 m in its lifetime. What is the speed of the muon relative to Earth? A) 0.821c
  B) 0.681c
  C) 0.601c
  D) 0.551c
  E) 0.335c

Question 2

A pion is an unstable particle that has an average lifetime of 2.55  10-8 s.
 
  This is the time interval between its creation in a nuclear process and its extinction into decay products, as measured in a frame of reference at rest with respect to the pion. An average pion is traveling at 0.230c relative to Earth. How far does it travel in its lifetime, relative to Earth? A) 2.07 m
  B) 1.81 m
  C) 2.23 m
  D) 3.22 m
  E) 3.50 m

[zhanghao]

Answer to Question 1

C

Answer to Question 2

B

[humphriesbr@me.com]

Gracias!

[Bigfoot1984]

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