Use the phasor method, described in conjunction with Fig. 7.17, to explain how two equal-a...

Use the phasor method, described in conjunction with Fig. 7.17, to explain how two equal-amplitude waves of sightly different frequencies generate the beat pattern shown in Fig. 7.16 or Fig. P.7.16a. The curve in Fig. P.7.16b is.a sketch of the phase of the resultant measured with respect to one of the constituent waves.

Explain its main features. When is it zero and why? When does the phase change abruptly and why?

Figure P.7.16

(a).

(b).