Some help will be appreciated. I just know that conservation of string follows here. But relating velocities troubling me.
P.S Don't panic that it is copied from some very hi fi book. It can be found in any Fiitjee's paper.
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1 Answers
rahulsidhu
·2011-11-10 04:24:02
Draw a perpendicular from O' to AB, lets call the point of intersection as P.
let l be the length of the string.
l = A'O' + O'O
= A'O' + √ AA'2+OP2
differentiate w.r.t time
dl/dt = 0 = v1 + (1/2)*[2OP(v2-v1)]/√ AA'2+OP2
OP/√ AA'2+OP2 = cos(alpha)
thus v2 = v1(cos(alpha)-1)