A ring of mass m can slide on a friction less rod. The ring is attached to a string which goes over a nail (frictionless) making an angle theta (with the rod) and the other end is tied to a block of mass 2m.

Calculate the acceleration of the block and the ring as a function of theta..

Question

A ring of mass m can slide on a friction less rod. The ring is attached to a string which goes over a nail (frictionless) making an angle theta (with the rod) and the other end is tied to a block of mass 2m. 

Calculate the acceleration of the block and the ring as a function of theta..

anonymous · Answer

|dw:1408532533655:dw|

i want to know what is the relation between the rings horizontal acceleration and the blocks vertical acceleration

my gut says  a_block = a_ring cos(theta)

but the solution is given the other way a_ring = a_block Cos(theta)

and either ways.. i dunno how to prove it :P