You are supplied with three identical rods of same length and mass. If the length of each rod is `2pi`. Two of them are converted into rings and then placed over the third rod as shown in figure. If point A is considered as origin of the coordinate system the coordinate of the center of mass will be (you may assume AB as x-axis of the coordinate system).

Options

A. `(pi/2,1/3)`
B. `(pi/2,2/3)`
C. `(pi,1/3)`
D. `(pi,2/3)`

Answer

D

Explanation

`2piR = 2pi therefore R=1`
`y_(CM) = (m xx 0 + m xx 1 + mxx1)/(m+m+m) = 2/3`
`x_9CM) = (m(pi)+ m(0) + m(2pi))/(m + m + m) = pi`