I think, the inertia (or simply the mass) of the mass that's above the mass center acts as counterweight(?) to the mass part below. You can use it, controlling its (the mass part above's) position with the eyes to `take´ the mass center straight above its basis contact, but acting on and sustaining always the mass center. [But I've only casually balanced stuff only with hands, fingers, foot yet] See also: [german:] https://de.wikipedia.org/wiki/Gleichgewicht_%28Physik%29#Mechanik . http://www.tphys.uni-heidelberg.de/~huefner/PhysikUeberall/V04S.pdf , chapter 3 [ found with "physik des balancierens"]: Pencil vs broom: a long prop falls slowlier! That's why it's easier to balance. Dynamical equilibrium; See also: "metastability" (stable unto a certain point, then unstable), but alas, no example or relation to prop balancing found, so that is maybe a specific term for particle physics and chemistry, and might not apply for mechanics. [Sorry for german, but didn't find corresponding english info.]
↧