Calculating Muon Decay in Relativity: A Scientific Analysis

AI Thread Summary
The discussion revolves around calculating muon decay in the context of relativity. A muon, with a rest lifetime of 2.20 x 10^-6 seconds, is analyzed for its behavior at a speed of 0.99c. According to Newtonian mechanics, it would travel approximately 653.4 meters before decaying. However, in the Earth's frame of reference, the muon's lifetime extends to 1.56 x 10^-5 seconds, allowing it to travel about 4633.2 meters. The participant expresses initial uncertainty about part (c) but later confirms the calculations are correct.
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Homework Statement


A muon has a lifetime of 2.20 x 10^-6 s when at rest, after which time it decays into other particles.
a) If the muon was moving at 0.99c, how far would it travel before decaying into other particles, according to Newtonian mechanics?
b) How long would the muon last, according to an observer in Earth's frame of reference who viewed the muon moving at 0.99c?
c) How far would the muon actually travel, when viewed moving at 0.99c?

2. The attempt at a solution
a) 0.99c(3 x 10^8c) = 2.97 x 10^8
(2.97 x 10^8 m/s)(2.2 x 10^-6 s) = 653.4 m

b) Δtm = Δts/√(1-v^2/c^2)
Δtm = 2.2 x 10^-6 s / √(1-(0.99c)^2/c^2)
= 2.2 x 10^-6 s / √ (1 - 0.9801) = 1.56 x 10^-5 s

c) (2.97 x 10^8 m/s)(1.56 x 10^-5 s) = 4633.2 m

Not sure about c) any suggestions are appreciated thank you
 
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Look good to me! :smile:

Is there something about part (c) that makes you unsure?
 
Actually after giving it another look I got around it so thanks for your confirmation
 
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