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?

The cheetah is considered the fastest running animal in the world. cheetahs can accelerate to a speed of 20.1 m/s in 2.50 s and can continue to accelerate to reach a top speed of 28.1 m/s. assume the acceleration is constant until the top speed is reached and is zero thereafter.1) starting from a crouched position, how long does it take a cheetah to reach its top speed? (express your answer to three significant figures.) s2) how far does it travel in that time? (express your answer to three significant figures.) m3) if a cheetah sees a rabbit 120 m away, how long will it take to reach the rabbit, assuming the rabbit does not move? (express your answer to three significant figures.)