Question

3. A U.S. quarter with a mass of 5.67 grams is sitting on a 12-inch (30.48 cm) diameter vinyl record on an old 78 revolution-per-minute (rpm) record player's turntable. The quarter is half way between the record's center and outer edge and the coefficient of static friction (As) between the quarter and record is 0.35. The record player (aka Victrola) has an old motor and it takes 90 seconds to speed up to 78 rpm from zero rpm. a. How long from the time rotations starts until the quarter starts to slip off the record, and b. How far is the cumulative distance the quarter has traveled in this time? c. If the turntable and record can be modeled as a single 0.75 kg disc, how much torque was required to achieve the

Answer 1

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