# Muon Experiment

The measurement of the flux of muons at the Earth's surface produced an early dilemma because many more are detected than would be expected, based on their short half-life of 1.56 microseconds. This is a good example of the application of relativistic time dilation to explain the increased particle range for high-speed particles.

## Non-Relativistic

 Non-relativistic Relativistic, Earth observer Relativistic, muon observer
 Comparison Comments on comparison Vary parameters

 Numerical example from laboratory setting
 What is a muon? Some history
 A brief overview of time.
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# Muon Experiment

## Relativistic, Earth-Frame Observer

 Non-relativistic Relativistic, Earth observer Relativistic, muon observer
 Comparison Comments on comparison Vary parameters
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# Muon Experiment

## Relativistic, Muon-Frame Observer

 Non-relativistic Relativistic, Earth observer Relativistic, muon observer

 Comparison Comments on comparison Vary parameters
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# Muon Experiment

## Comparison of Reference Frames

 Non-relativistic Relativistic, Earth observer Relativistic, muon observer

 Comparison Comments on comparison Vary parameters
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# Muon Experiment

## Comparison of Reference Frames

 In the muon experiment, the relativistic approach yields agreement with experiment and is greatly different from the non-relativistic result. Note that the muon and ground frames do not agree on the distance and time, but they agree on the final result. One observer sees time dilation, the other sees length contraction, but neither sees both. These calculated results are consistent with historical experiments.
 Non-relativistic Relativistic, Earth observer Relativistic, muon observer

 Comparison Comments on comparison Vary parameters
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# Muon Experiment

## Vary Parameters

 The calculation will be considered from the Earth frame of reference. The length is then unaffected since it is in the Earth frame. The halflife is in the muon frame, so must be considered to be time dilated in the Earth frame. You may substitute values for the height and the muon speed in the calculation below.

Length L0 = x 10^ meters.

If the muon speed is v = c

then the relativity factor is γ =

The time-dilated halflife is x 10^ seconds.

The time to reach the Earth is t = L0/v = x 10^ seconds.

This is halflives,

leaving a population of out of a million.

 Non-relativistic Relativistic, Earth observer Relativistic, muon observer

 Comparison Comments on comparison Vary parameters
Index

Relativity concepts

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