The reality of time dilation was verified by experiment performed respectively in 1941 and 1963. An elementary particle, the muon(μ), decays into other particles. With N muons at t=0, the number remaining at a later time t is N1 = N * e^(-t/τ), where τ=2.2μs is called the mean lifetime. Among other sources, muons are produced in the upper atmosphere form the bombardment of cosmic ray protons and, then, move with speed of v=0.995c. The experiment involved the comparison of the number N2 of muons detected at an altitude of 2000m with the number N3 detected at sea level, as shown in Fig.2.
Question 1 :
Please verified the experimental results of N3/N2 = 0.7.
Question 2 :
Please prove that for an observer moving together with muon he obtains also N3/N2=0.7.(Hint : use length contraction)
更新1:
Fig.2 在這裡 :
http://www.badongo.com/pic/6315159
左邊的代號依序算下來為題目中的 N N2 M3
圖中高度為2000m
圖片較不清晰煩請見諒
