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A rod OA rotates about a horizontal axis...

A rod OA rotates about a horizontal axis through O with a constant anti-clockwise velocity `omega=3 rad//s.` As it pases the positions `theta=0^(@)` a small block of mass m is placed on it at a radial distacne r=450 mm If the block is observed to slip at `theta=50^(@)` the coefficient of static friction bewteen the block and the rod is (Given that ,`sin50^(@)=0766,cos 50^(@)=0.64`)

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The correct Answer is:
`mu = (3)/(16)`
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