Conical Pendulum

1. Feb 25, 2009

nokia8650

http://img25.imageshack.us/my.php?image=77494342.jpg

I can do the first part, however am unsure of how to deduce the motion cannot take place unless the inequality is satisfied. Can someone please explain this part?

Thanks

Last edited: Feb 25, 2009
2. Feb 25, 2009

Office_Shredder

Staff Emeritus
Assume the opposite inequality holds, and plug it into the equality you got (giving you an inequality) and see if a contradiction pops up

3. Feb 25, 2009

nokia8650

ahh yes, i see, thank you!