Angular Momentum of Collapsing Star · PhysicsBowl 2022 #32
Physics · mechanics
Problem
A star initially has a radius of 6 x 10⁸ m and a period of rotation about its axis of 30 days. Eventually, it collapses to form a neutron star with a radius of only 1 x 10⁴ m and a period of 0.1 s. Assuming that the mass has not changed, find the ratio of initial and final angular momentum of the star.
a. 15.92 b. 214.6 c. 103.1 d. 442.1 e. 138.9