Question

what is centre of mass for uniform rod

Answer 1

the centre of the axis of the cylindrical iron rod

Answer 2

$\huge\boxed{\texttt{\fcolorbox{red}{aqua}{Hey Mate}}}$

In physics, the center of mass of a distribution of mass in space is the unique point where the weighted relative position of the distributed mass sums to zero, or the point where if a force is applied it moves in the direction of the force without rotating