Three identical spheres each of radius `R` are placed touching each other on a horizontal table as shown in figure. The co-ordinates of centre of mass are :
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Options

A. `(R,R)`
B. `(0,0)`
C. `((R )/(2), (R )/(2))`
D. `(R, (R)/(sqrt(3)))`

Answer

D

Explanation

(d) `x_(cm) = (m xx 0 + m xx 2R + mR)/(3 m) = R`
`y_(cm) = (m xx 0 + m xx 0 + mR sqrt(3))/(3 m) = (R)/(sqrt(3))`.
.