Hey Bruce, I hope this isn't too forward but I'm having a little difficulty with a physics problem

and I noticed you held a degree in physics.
I posted the link and worked it out as best as I could, but noone seems to be replying just yet. So I just thought I'd throw you the link and if you had a few minutes to check it over for me that would be really great, thanks if you can!
regards,
Chris
http://www.physicsforums.com/showthread.php?t=588460