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xpoisnp

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If you were to move your hand towards the edge of the face and poke in the SAME forward direction, now the cube would gain some amount of spin and would therefore not move away from you as fast.

My question is: given a force applied to an object suspended in zero gravity, what portion of that force will be applied to the object's angular acceleration and what proportion to its lateral acceleration?

I'm most interested in two-dimensional examples, so you can imagine the same experiment performed on a square with evenly distributed mass on a 2D plane, where all the force vectors being applied to the square are in that plane. With that, any force vector can be divided into two component vectors: the vector pointing directly towards (or away from) the object's center of mass from the point of contact and the vector perpendicular to it. Obviously the component vector pointing directly towards (or away from) the object's center of mass won't ever contribute to angular acceleration, so my question then becomes what percentage of a vector perpendicular to the vector between the point of contact and the object's center of mass will be applied to its angular acceleration?

I expect the answer is as simple as "100% will be applied to angular acceleration" but I haven't convinced myself of that yet. And if it is that simple, I imagine adding friction makes things more interesting, so given coefficients of kinetic friction for angular and lateral movement, is it possible to calculate the portion of force perpendicular to the center of mass of the object that gets applied to angular acceleration versus lateral acceleration?

Oh and a WONDERFUL THANKS to anyone able to help me with this. I've been mulling this over for a while and just need good convincin' more than anything else!