Equal mass spinning about a common x and y axes?

[Robin07]

What happens when you have equal mass that is spinning about a common x and y axes as well as at the same rate(rpm)?

Now I use the term mass, understanding that this is the same in a vacuum as well as within our gravitational field. I may stand corrected here.

I've often wondered about the gyroscopic effect that is realized when you spin a bicycle wheel at a given rate and hold the whole assembly by either axle, it seems to defy gravity. As I understand it. If you can imagine the wheel cut in half through its center on a vertical plane. The right hand sides weight is being thrown down and the left hand sides weight is being thrown up effectively canceling each other out. Which leaves gravity being the only force acting apon it. Hence, if you let it go, it will crash to the ground. The total mass has not changed. Now if you could imagine, you then take this spinning wheel and rotate it in a horizontal plane at he same or different rates? What can be expected?

 

[Navin A S]

Well, when you have two objects of equal mass spinning about a common x and y axes at the same rate (rpm), the effect is called precession. This means that the combined systems will rotate around its center of gravity in a circular motion. This is due to the fact that each object has its own angular momentum, and when they are spinning at the same rate, their angular momentum vectors are pointing in the same direction. As a result, the combined system will move in a circular motion.