# Given the following information, what would the star's rotation speed be?

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Suppose a star the size of our Sun, but with mass 3.0 times as great, were rotating at a speed of 1.0 revolution every 11 days. If it were to undergo gravitational collapse to a neutron star of radius 15 km, losing three-quarters of its mass in the process, what would its rotation speed be

Assume that the star is a uniform sphere at all times, and that the lost mass carries off no angular momentum.

Suppose a star the size of our Sun, but with mass 3.0 times as great, were rotating at a speed of 1.0 revolution every 11 days. If it were to undergo gravitational collapse to a neutron star of radius 15 km, losing three-quarters of its mass in the process, what would its rotation speed be

Assume that the star is a uniform sphere at all times, and that the lost mass carries off no angular momentum.

##### 1 Answer

#### Explanation:

**Angular Momentum Conservation**: In the absence of an external torque, the net angular momentum of a system remains conserved.

The Moment-of-Inertia of a sphere of mass

**A milli-second Pulsar?**