QCEVault

Special relativity — Question 128

Original QCE Vault practice · 5 marks

Q128 · Practice questionComplex familiar5 marks

QUESTION 128 (5 marks)

An unstable particle has a proper mean lifetime of 1.601.60 microseconds and moves at 0.940c0.940c relative to a laboratory.
a)
Calculate the Lorentz factor and the mean lifetime measured in the laboratory.
[2 marks]
b)
Calculate the mean laboratory distance travelled.
[2 marks]
c)
Explain why using the proper lifetime directly in the laboratory underestimates the distance.
[1 mark]
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