A common source of frustration when I'm at work is the fact that my rolling office chair's wheels rotate whenever I push it forward or backward from my desk, which can cause it to bump my computer tower or any other object on the floor nearby. This happens no matter how carefully I avoid turning my torso, or how straight back I push.
What physical phenomenon causes office chairs to rotate in this way? It has five wheels, if that's important.
My suspicion is that there is some interaction among the friction forces of the wheels on the ground that gives rise to this behavior, but I don't understand how to connect the dots from "opposite the force of the push" to "circularly about the support column".
This is different from other physics.se office chair questions like these three because I am asking about the rotation along the vertical axis of the wheelbase, not why the chair has five wheels or how it can move without my feet on the ground.