When a star collapses it significantly shrinks in size and spins up. Consider a star with a mass of M = 2.2×1030 kg and an initial radius of R; = 6.8×105 km. If the initial period of rotation of the star is T₁ = 28.9 days, find the new rotational period after it collapses to a final radius of Rf = 6.8×10³ km. Treat the star before and after the collapse as a solid sphere with uniform mass distribution (which is not true, of course, but good enough for an estimation). The new rotational period of the star, Tf = Units km Find the ratio between the final and initial rotational kinetic energies of the star. The factor by which the kinetic energy of the star increases, KE₁f/KE₁ = The work done by gravity, W = || X The increase in the rotational kinetic energy of the star comes from gravity. How much work is done by the gravity force while collapsing the star? Units Select an answer Units N

When a star collapses it significantly shrinks in size and spins up. Consider a star with a mass of M = 2.2×1030 kg and an initial radius of R; = 6.8×105 km. If the initial period of rotation of the star is T₁ = 28.9 days, find the new rotational period after it collapses to a final radius of Rf = 6.8×10³ km. Treat the star before and after the collapse as a solid sphere with uniform mass distribution (which is not true, of course, but good enough for an estimation). The new rotational period of the star, Tf = Units km Find the ratio between the final and initial rotational kinetic energies of the star. The factor by which the kinetic energy of the star increases, KE₁f/KE₁ = The work done by gravity, W = || X The increase in the rotational kinetic energy of the star comes from gravity. How much work is done by the gravity force while collapsing the star? Units Select an answer Units N

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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