Question

Consider the two waves shown in Fig. 12–31. Each wave can be thought of as a superposition of two sound waves with slightly different frequencies, as in Fig. 12–18. In which of the waves, (a) or (b), are the two component frequencies farther apart? Explain.

Short answer

The two-component frequencies are farther apart in wave (a).

Step-by-step solution

Meaning of beat frequency

The beat frequency can be defined as the number of pulsations heard in one second when two sound waves of different frequencies interfere.

Comparison of wave (a) and wave (b)

The beat frequency is the difference between the two-component frequencies, so since (a) has a higher beat frequency, the component frequencies are farther apart in (a).