What's the word for ‘the point at which an object loses balance’?

I'm trying to think of a formal word to describe the "tipping point" of an object.

This would be the same point at which an object would be perfectly balanced.

Solution 1:

Are you looking for the center of gravity?

An object will balance when its center of gravity (the place where all of its mass, on the average, resides) is over the point of support. The larger the base, the more stable the object is.

Source - Exploratorium

Solution 2:

A fulcrum is the pivot point for a lever; but it can also be used as the balancing point of an object.

Physics the point on which an object balances or turns [Macmillan]

A simple diagram to illustrate:

bvg8science.wikispaces.com