Three identical balls each of radius 10 cm and mass 1 kg each are placed touching one another on a horizontal surface. Where is their centre of mass located?

Three identical spheres each of radius R are placed touching each oother on a horizontal table. Where is the centre of mass of the system located?

Four identical spheres each of radius 10 cm and mass 1 kg are placed on a horizontal surface touching one another so that their centres are located at the corners of square of side 20 cm. What is the distance of their centre of mass from centre of either sphere ?

Four identical spheres each of radius 10 cm and mass 1 kg are placed on a horizontal surface touching one another so that their centres are located at the corners of square of side 20 cm. What is the distance of their centre of mass from centre of either sphere ?

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