# Homework Help: Relativity & decay

1. May 5, 2010

### Starwanderer1

Well, I dont want the solution but a few ideas to start solving this..

Two unstable particles move in the reference frame M with a velocity v=0.992c. The distance between them in this reference frame is l=110 m. At a certain moment both particles decay simultaneously in this frame. What time interval between the moments of decay of the 2 particles will be observed in the frame ? Which particle decays later in this frame?

Please tell me a bit on the concept of particle decay in a relativistic case like this..

2. May 5, 2010

### Mentz114

I don't know if I'm misreading this. You say the decays are simultaneous when seen from M. So the question "Which particle decays later in this frame?" ( M ?) is a bit pointless. There are frames where either particle will be seen to decay before the other.

3. May 5, 2010

### Staff: Mentor

Looks to me like the OP 'cut and pasted' this problem from somewhere and in the process several key words were dropped.