In: Physics
The proper mean lifetime of a muon is 2.2ms. Muons in a beam are traveling through a laboratory at 0.95c.
1. What is their mean lifetime as measured the laboratory?
2. How far do they travel, on average, before they decay?
Please show expressions, work, and a proper explination!!!
Given, muon proper mean life time 'to' = 2.2 ms
velocity 'v'= 0.95C ( C is the velocity of light in vaccum = 3 x 10^8m/s)
a) mean life time = (r )* (to) where, r = 1/[square root(1 - v^2/c^2)
therefore, r = 1/squareroot(1- (0.95)^2)
= 1/ 0.31224 = 3.2
mean life time = 3.2 * 2.2 = 7.04 ms
b) distance = velocity * mean life time
= 0.95C * (7.04 x10^-3)
= 0.95 * (3 x 10^8)*(7.04 x 10^-3)
= 20.06 x 10^5 m
= 2006 km