1. The problem statement, all variables and given/known data A physics student drops a vibrating 421 Hz tuning fork down the elevator shaft of a tall building. The temperature in the shaft is 20 °C. When the student hears a frequency of 392 Hz, how far has the tuning fork fallen? fS = 421 Hz fL = 392 Hz VSOUND = 343 m/s 2. Relevant equations Doppler Equation: fL = fs(VSOUND + Vlistener)/(VSOUND + VSource) 3. The attempt at a solution I solved for the velocity of the source and got 25.38 m/s but I don't really get how I would apply it to this problem. If only I had time.