[SOLVED] Forece Between Two Hemispheres I am trying to study for my classical mechanics final, and the prof hinted that this problem would be on the final. Two uniform rigid hemispheres eachof mass M and radius a are placed in contact with each other so as to form a complete sphere. Find the forces necessary to pull the hemishperes apart I've been mulling over it for three days now trying to figure out how to solve it. I tried used spherical cooridnated to solve it but I am not sure where to begin. I possibly could find the force due to a sphere of Mass 2M, but that does not help me in finding the force required to separate the hemispheres. The back of the book gives the soloution, but thats useless to me if I can't get to it. How would I go about to begin solving the problem?