Lets suppose we have a planet made from two half-sphere with the same radius (R) made from matter with different density.(adsbygoogle = window.adsbygoogle || []).push({});

The left-half-sphere is made from rocks (5gr/cm3) and the right-half-sphere is made from iron (8gr/cm3).

Then we pour water on up to about one-tenth of the sphere volume.

1. Will the water collect up to a surface with the same gravitational acceleration or collect to up to a surface with the same potential energy per mass level ?

a. assuming the planet isn't spinning

b. assuming the planet is spinning along the rocks-iron line

c. assuming the planet is spinning along a line perpendicular to the rocks-iron line

2. What is a class of geometric shape experiencing the same gravitational acceleration magnitude given the position and mass of several source of gravity (lets assume it is point-mass for simplicity)? ( Yes, I know the shape would vary a lot depending on the system. I want to know whether there is any standard name for these class of geometry. )

I need these information in order to calculate the shape of Rocheworlds and Roche-Klemperer-primary.

Thanks for your help,

Fendy

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# How will the water surface of this planet looks like ?

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**