# Effect of centrifigual force on a gavity bound object

1. Aug 31, 2008

### soandos

is there a relation between the density of a sphere spinning at a given rate and the degree by which the minor axis shrinks?
if there is a relation, what is it.
thanks a lot

Last edited: Aug 31, 2008
2. Sep 1, 2008

### HallsofIvy

Staff Emeritus
That will depend very much on the elasticity of the sphere.

3. Sep 1, 2008

### pixel01

The faster the sphere spins, the less dense the sphere is. It seems to be proportional to the length of the minor axis.

4. Sep 1, 2008

### soandos

assuming though that i have two spheres made of the same material, would the differing densities make a difference?
also, i think that pixel you misunderstood. i realize that as it spins it should get more dense as the volume is shrinking, but that is not my question.

Last edited: Sep 1, 2008
5. Sep 3, 2008

### granpa

I dont think gravity has much to do with it. its a GRAVITY bound sphere. it would form an ellipsoid. the denser the object the stronger the gravity so yes for any given rotation rate the degree of flattening will be less.

i presume this is about the neutron star you mentioned in your other post.

6. Sep 3, 2008

### soandos

i realized that this would happen. i just do not know by how much.