The centroid is centre of mass of a two-dimensional planar lamina or a three-dimensional solid. The mass of a lamina with surface density function 
is
is |
(1)
|
and the coordinates of the centroid (also called the centre of gravity) are
 |  |  |
(2)
|
 |  |  |
(3)
|
The centroid of a lamina is the point on which it would balance when placed on a needle. The centroid of a solid is the point on which the solid would "balance."
Dear Student friends after having a look at the above definition and equation you may get a view that it would be very difficult to find centroid of a lamina, but its really simple..... go through the post and revert with your comments.....
