# Question

An ice skater spinning with outstretched arms has an angular speed of 4.0 rad/s. She tucks in her arms, decreasing her moment of inertia by 7.5%.

(a) What is the resulting angular speed?

(b) By what factor does the skater’s kinetic energy change? (Neglect any frictional effects.)

(c) Where does the extra kinetic energy come from?

(a) What is the resulting angular speed?

(b) By what factor does the skater’s kinetic energy change? (Neglect any frictional effects.)

(c) Where does the extra kinetic energy come from?

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