Question

The nebular theory states that star systems form by the gravitational collapse of a cloud of gas and dust that, to match observations, must flatten into a disk within which planets can form. Why would this flattening occur? Consider the law of conservation of angular momentum, which states that a quantity related to the size of an object (its moment of inertia) times the speed of rotation (angular speed) has to remain the same at all times as long as no outside forces act on that object. Based on this law, if a collapsing cloud is isolated in space with no external forces, what must happen to it as its size decreases?

Answer 1

In order for a planet to form there must be a strong force present to hold the material together and for that to happen a disk is to be formed in order for the dust cloud to enter into a phase of Quasi equilibrium in which the centrifugal force is equal to the gravitational force thus providing for matter to bind together and allow for it to be converted into planets.

The cloud will spin faster i-e as the size will go on decreasing the angular momentum will increase(reduction in radius) and it will start spinning faster.

Step-by-step explanation: