Why does a cone-shaped object, when placed on its side on a flat surface, rotate about the end with a smaller diameter?

Question

Examples include a light bulb, a screw, a nail, etc.

I intuitively know how these objects behave, but I’m having trouble putting it into words/reasoning about it.

Is it because of the tilt? The diameter difference (this causes the tilt)?

In: 9

Answer 1

Take a light bulb lying on its side. The bulb itself has, let’s say, twice the diameter as the base. If now the object rotates, every part of it will do the same amount of rotation, or the same angle. When doing this, the bulb will move twice as far as the base at the respective point of contact with the surface. This is just like if you would walk taking twice as big steps with one of the legs, resulting in a curve.