A student investigating circular motion places a dime 10 cm from the center of a 33 1/3-rpm record on a turntable. The record player can accelerate at 1.42 rad/s squared. The student notes that the dime slides outward 2.25 s after she has switched on the turntable. (a) Why does the dime slide outward? (b) What is the coefficient of static friction between the dime and the record?