Question

Give the location of the centre of mass of a

1. sphere,
2. cylinder,
3. ring, and
4. cube,

each of uniform mass density. Does the centre of mass of a body necessarily lie inside the body?

Answer 1

For objects with uniform mass density, such as a sphere, cylinder, ring, and cube, the centre of mass is located at their respective geometric centres. This is due to the symmetrical distribution of mass throughout these objects. However, the centre of mass of a body does not necessarily have to lie within the physical material of the body. A notable example of this is a circular ring, where the centre of mass is at the geometric centre of the ring but in an area where there is no physical mass.