College Physics II – Mechanics, Sound, Oscillations, and Waves
Definition
An expanding rotating nebula is a vast cloud of interstellar gas and dust that is expanding outward while also rotating around a central axis. This phenomenon is a crucial step in the formation of new stars and planetary systems within the universe.
congrats on reading the definition of Expanding Rotating Nebula. now let's actually learn it.
As an expanding rotating nebula contracts due to gravity, it conserves its angular momentum, causing the rotation to speed up.
The conservation of angular momentum is a fundamental principle that governs the formation and evolution of stars and planetary systems.
The increased rotation of the contracting nebula leads to the formation of a protostar at the center and a surrounding accretion disk, from which planets can eventually form.
The expansion of the nebula is driven by the outward pressure of the gas and the energy released during the gravitational collapse.
The rate of expansion and rotation of the nebula are key factors in determining the final properties of the resulting star system, such as the number and arrangement of planets.
Review Questions
Explain how the conservation of angular momentum affects the formation of an expanding rotating nebula.
As an expanding rotating nebula contracts under the influence of gravity, the conservation of angular momentum causes the rotation to speed up. This is because the total angular momentum of the system must be conserved, and as the radius of the nebula decreases, the rotational velocity must increase to maintain the same angular momentum. This increased rotation is a crucial step in the formation of a protostar at the center of the nebula and the surrounding accretion disk, from which planets can eventually form.
Describe the role of gravitational collapse in the evolution of an expanding rotating nebula.
The gravitational collapse of an expanding rotating nebula is a key process in the formation of stars and planetary systems. As the massive cloud of gas and dust contracts under its own gravity, the conservation of angular momentum causes the rotation to speed up. This increased rotation leads to the formation of a protostar at the center of the nebula and the creation of an accretion disk surrounding the protostar, from which planets can eventually form. The rate of this gravitational collapse and the resulting rotation are crucial factors in determining the final properties of the star system.
Analyze how the expansion and rotation of an expanding rotating nebula contribute to the formation of a new star system.
The expansion and rotation of an expanding rotating nebula are essential for the formation of a new star system. The expansion of the nebula is driven by the outward pressure of the gas and the energy released during the gravitational collapse. As the nebula contracts under its own gravity, the conservation of angular momentum causes the rotation to speed up, leading to the formation of a protostar at the center and an accretion disk surrounding it. The rate of expansion and rotation of the nebula determine the final properties of the resulting star system, such as the number and arrangement of planets. This process is a fundamental step in the creation of new stars and planetary systems within the universe.
Related terms
Angular Momentum: The measure of an object's rotational motion, determined by the object's mass, velocity, and distance from the axis of rotation.
Gravitational Collapse: The process by which a massive cloud of gas and dust contracts under its own gravity, leading to the formation of stars and planetary systems.
Protostar: A young, collapsing cloud of gas and dust that is in the early stages of becoming a star.