Chapter 13 Note if f2<f1 object is moving away and Vo= Vs/(f2/f1)-Vs
If towards (f2>f1) Vo=Vs-Vs(f2/f1)
64c) 1925 Hz 65 b) 1586Hz
67 86 m/s 68 38 m/s 70 a) (use Vs=340m/s) 1975 Hz b) 1654 Hz
71 same as 70, doesn't matter what or who is moving.