Three objects of mass 1 kg each are placed at corners of a right-angled triangle AOB as shown in the figure. Consider ‘O’ as the origin and OA = OB = 1m. Determine the position of the centre of mass of this system.

1/3 (i+ j) m

Sum of masses = 1 + 1 + 1 = 3

x-coordinate : (1 x 0+1 x 0 + 1 x 1)/3 = 1/3

y-coordinate : (1 x 1 + 1 x 0 + 1 x 0)/3 = 1/3

Position of centre of mass = 1/3 (i + j) m.