Page 35 - Master Handbook of Acoustics

FIGURE 1-11 A study of the combination of sine waves that are not in phase. (A) The fundamental
frequency f . (B) The second harmonic f with twice the frequency and half the amplitude of f 1
1
2
advanced 90° with respect to f . (C) The combination of f and f obtained by adding ordinates point
1
2
1
by point. (D) The third harmonic f3 with phase 90° behind f , and with half the amplitude of f . (E)
1
1
The sum of f , f , and f3. Compare this resulting waveform with that of Fig. 1-9E. The difference in
1
2
waveforms is due entirely to the shifting of the phase of the harmonics with respect to the
fundamental.