PHYSICS · Subjective · AP · Physics 1: Algebra-based · Energy and Momentum of Rotating Systems · Energy and Momentum of Rotating Systems
Problem
A star rotates once every 30days while its radius is 7.0×108m. Later it collapses to a white dwarf with radius one-tenth the original and no loss of mass. Assuming no external torque and that the star behaves as a uniform sphere, determine its new rotation period in hours.