What structural consequence arises from rapid rotation during cloud contraction?

Formation of a flattened protoplanetary disk

As the initial solar nebula cloud collapses inward under gravity, the conservation of angular momentum dictates that its rate of rotation must increase significantly. This rapid spin creates a strong centrifugal force directed outward in the plane perpendicular to the axis of rotation. This outward force resists the gravitational collapse along that rotational plane, while gravity continues to pull material inward along the axis. The result of this differential force is the transformation of the nearly spherical cloud into a highly flattened, spinning structure known specifically as a protoplanetary disk. This flattened geometry is essential because it establishes the co-planarity observed in the orbits of the resulting planets.