To measure the magnitude of the acceleration due to gravity g in an unorthodox manner, a student places a ball bearing on the concave side of a flexible speaker cone (Figure 1). The speaker cone acts as a simple harmonic oscillator whose amplitude is A and whose frequency f can be varied. The student can measure both A and f with a strobe light. Take the equation of motion of the oscillator as y(t)=Acos(ωt+ϕ), where ω=2πf and the y axis points upward. The frequency is slowly increased. Once it passes the critical value fb , the student hears the ball bounce. There is now enough information to calculate g . What is g ?