Rotating a Rectangle on Different Anchor Points

I really frustrated on this problem
imagine a set of rectangles, then a ball hit one of them.
I tried to show the boxes reaction which some fall on the ground and some rotating in different angles to finally stop at a point.
My problem is I cannot move the anchor point without moving the position (I known it is apparent position which is logical to expect to move, whether with pan behind tool or changing anchor point numerically).
But is there anyone who did something like this animation and I want to ask how did you do that.
Please watch my animation which I finally did with tedious hours of work with animating both position and rotation to retain a layer in its position in different angles rotation.
I would be truly grateful if somebody shed a light to my mind to solve this kind of problems in a better way.

The Example I did:
https://vimeo.com/133887962

Newton is a great suggestion in this case. Though if you're interested in using more than one 'anchor point' in the future you can parent your layer to a series of Nulls, each one can serve as a center of rotation.

Darby Edelen