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11 Dec 2019

Muons are unstable subatomic particles that decay to electrons with a mean lifetime of 2.2 μs . They are produced when cosmic rays bombard the upper atmosphere about 11.4 km above the earth's surface, and they travel very close to the speed of light. The problem we want to address is why we see any of them at the earth's surface.

What is the greatest distance a muon could travel during its 2.2 μs lifetime?

According to your answer in part A, it would seem that muons could never make it to the ground. But the 2.2 μs lifetime is measured in the frame of the muon, and muons are moving very fast. At a speed of 0.999 c, what is the mean lifetime of a muon as measured by an observer at rest on the earth?

Express your answer using two significant figures.

How far would the muon travel in this time?

Express your answer using two significant figures.

From the point of view of the muon, it still lives for only 2.2 μs , so how does it make it to the ground? What is the thickness of the 11.4 km of the atmosphere through which the muon must travel, as measured by the muon?

Express your answer using two significant figures.

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Ankit Lal
Ankit LalLv10
24 Mar 2021

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Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

Related questions

How fast can a racecar travel through a circular tum without skidding and hitting the wall? The answer could depend on several factors:

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In this project, we investigate this question for NASCAR racecars at the Bristol Motor Speedway in Tennessee. Before considering this track in particular, we use vector functions to develop the mathematics and physics necessary for answering questions such as this.

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The next three questions deal with developing a formula that relates the speed to the banking angle .

Now that we have a formula relating the maximum speed of the car and the banking angle, we are in a position to answer the questions like the one posed at the beginning of the project.

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The coefficient of friction for a normal fire in Elly conditions is approximately . Therefore, we assume the coefficient for a NASCAR tire in dry conditions is approximately .

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