Concept explainers
(a)
In which of the reference frames are the proper time and the rest length between the two events measured if High-speed cosmic rays strike atoms in Earth's upper atmosphere and create secondary showers of particles. Suppose a particle in one of the showers is created 25.0 km above the surface traveling downward at 90.0% the
(b)
In the particle's reference frame how long after its creation does it take it to reach the ground?
(c)
In Earth's reference frame how long after creation does it take the particle to reach the ground?
(d)
That the times in parts (b) and (c) are consistent with time dilation?
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