# Homework Help: Muon Decaying particle

1. Jan 13, 2008

### Winzer

1. The problem statement, all variables and given/known data
The muon is an elementary particle that decays with a mean (rest) lifetime of 2.20E-6 s. A beam of muons has a speed of 0.600c. In the reference frame of the muon, how far does the laboratory travel in one mean lifetime?

2. Relevant equations
$$L=\frac{L_o}{\gamma}$$

3. The attempt at a solution
a. The muon has to travel (2.20E-6 s)(.60c)=396m seen from the muon
so isn't it $$L=\frac{L_o}{\gamma}$$ where $$\gamma=1.25$$
that would equall 316.8 m to the muon
b. 396 m

Last edited: Jan 13, 2008
2. Jan 13, 2008

### Winzer

anything?

3. Jan 14, 2008

### Winzer

Or maybe it is the muon that sees the lab travel 396m?

4. Jan 14, 2008

### Winzer

5. Jan 14, 2008

### Winzer

Don't be shy now