A table with smooth horizontal surface is placed in a cabin which moves in a circle of a large radius R (figure 7-E5). A smooth pulley of small radius is fastened to the table. Two masses m and 2m placed on the table are connected through a string going over the pulley. Initially the masses are held by a person with the strings along the outward radius and then the system is released from rest (with respect to the cabin). Find the magnitude of the initial acceleration of the masses as seen from the cabin and the tension in the string.



Let us solve this question intuitively. The resultant force on these blocks will make the whole block mass system move. The forces acting on these blocks are centrifugal force and tension.


But, here will not contribute to acceleration anyway. So,





Putting the values we get,



Now, if we consider the block m1 then we can find the equation of motion as,



Putting we get,




1