Relativistic centripetal force

[cornfall]

Rotation?

Do you remember that relativistic effect happen along the direction of motion?

What relativistic effect are you referring to?

 

[pervect]

the constant is 0.3*B, where B is measured in T, and p in GeV/c

Where is my suggested typo?

That forumula is widely used in particle physics.

Sorry, I misunderstood the question. It seems to me that you have two separate questions, though, if I'm understanding it correctly this time.

1) How do you compute the momentum of a particle, given its observed radius of curvature in a magnetic field of known strength. (You've supplied your own answer to this one, it looks right though I haven't double checked it)

2) What is the force (i.e. dp/dt) on that particle in the lab frame?

The answer gamma m v^2 / r is correct here as well with these assumptions.

Note that you have to specify a frame in order to ask what the 3-force is. One of the advantages of 4-forces is that they are geometric, frame-independent objects , but the magnitude of the 3-force definitely depends on the frame in which it is measured.

 

[malawi_glenn]

Sorry, I misunderstood the question. It seems to me that you have two separate questions, though, if I'm understanding it correctly this time.

1) How do you compute the momentum of a particle, given its observed radius of curvature in a magnetic field of known strength. (You've supplied your own answer to this one, it looks right though I haven't double checked it)

2) What is the force (i.e. dp/dt) on that particle in the lab frame?

The answer gamma m v^2 / r is correct here as well with these assumptions.

Note that you have to specify a frame in order to ask what the 3-force is. One of the advantages of 4-forces is that they are geometric, frame-independent objects , but the magnitude of the 3-force definitely depends on the frame in which it is measured.

The thing is that I don't have a question, I just wanted to add what I obtained to this discussion.

Maybe I should have written "I WAS trying to derive this forumula.." And then I played a bit, and also searched in some books etc to werify my steps, that's all. And I wanted to contribute with my "research" in this thread, where to OP seemed to find the expression i posted.