Find the centre of mass of a uniform triangula lamina.

Explanation

The lamina `(Delta "LMN")` may be subdivided into narrow strips each parallel to the base (MN) as shown in figure

By symmetry each strip has its centre of mass at its midpoint . If we join the midpoint of all the strips we get median LP . The centre of mass of the triangle as a whole therefore . has to lie on the median LP. Similarly , we can argue that lies on the point of concurrence of the medians , i.e on the centroid G of the triangle .