ABSTRACT
The lifetime of the muon must be measured in its own rest frame. Geo-
metrically, we have the triangle in Figure 7.1, the hypotenuse of which is
2c× 10−6 = 600 meters. this 3-4-5 triangle is easily seen to be 1000 meters, from which we can read off
v
c = tanhβ =
5 . (7.2)
PROBLEM 7.2. A rocket ship leaves Earth at a speed of 35c. When a clock on the rocket says 1 hour has elapsed, the rocket sends a light signal back to
Earth.
