The net force on an object is: F = ma The only force acting on the speck of dust as it is lays on the CD is centripetal force given by: F = (mv²)/r Equating the two ma = (mv²)/r We get: a = v²/r v is the linear velocity in this case; however, we can calculate only the angular velocity with the given data. Therefore, we must use: v = ωr; where ω = 2πf; f is the rotations per second f = 9500 / 60 f = 950/6 ω = 2π(950/6) ω = (950π)/3 v = (950π)/3 × 0.12 v = 38π a = (38π)²/0.12 a = 1.2 × 10⁵ m/s² To express this in terms of gravitational acceleration, we divide by the value of gravitational acceleration, 9.81 a = 1.2 × 10⁴ g
