center of mass question!

pras_quantum

can some one explain me why,center of mass of an object can lie outside the surface of the object also?

Doc Al

Why don't you explain why you think it cannot?

pras_quantum

actually i want to know when will it lie inside or outside the objects..so please explain.

Bob_for_short

If the body is not so spherically symmetric, for example, two equal balls touching, then the center of inertia is between them (at the touching point). If there are three balls, the center of inertia will be at the geometrical center of this figure. So it is possible if the body is not spherically symmetric but has a complicated form.

Doc Al

Consider a donut (with a hole in the middle). Where is its center of mass?

pras_quantum

thank you people for helping me...

arildno

Just another comment:

If you take the average of 10 (or some other quantity) numbers, pras_quant, must the average of those numbers be one of those numbers?