i am getting 42.89 degrees but it was not really very easy.
used T sin theta=m v^2/r and T cos theta= mg gave tan theta= v^2/ rg
but r is not given , so used l sin theta= r
thus tan theta * sin theta= v^2/ lg=given l= length of string
used tan theta= sin theta / cos theta , and wrote cos theta= root over (1- sin^2 theta) reducing the problem to one variable, sin theta. solved sin theta. one root was coming absurd. the other was good -used that one.
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Last edited by r.samanta; Oct 28th 2009 at 02:35 PM.
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