Beat frequency problem. Your ear simultaneously hears waves from different sources, so it can hear beats from the two speakers. In principle, the easiest way to measure the sound waves is to put a detector between the two speakers; however, in the experiment no detector is used to measure the wave field. Instead the voltages applied to the speakers are added electronically by the oscilloscope to simulate the true sound waves.

Suppose one speaker is driven at 570 Hz and the other at 554 Hz.

a. What is the beat frequency in Hz?
b. The average frequency in Hz?