Neutron Star Glitches. Occasionally, a rotating neutron star (see Exercise 10.41) undergoes a sudden and unexpected speedup called a glitch. One explanation is that a glitch occurs when the crust of the neutron star settles slightly, decreasing the moment of inertia about the rotation axis. A neutron star with angular speed ω0 = 70.4 rad/s underwent such a glitch in October 1975 that increased its angular speed to ω0 = ω0 + Δω, where Δω/ω0 = 2.01 × 10−6. If the radius of the neutron star before the glitch was 11 km, by how much did its radius decrease in the starquake? Assume that the neutron star is a uniform sphere.
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