Frequency of Beats/Mistake

Source Work

1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.)

2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.):

beats

Mistake

The frequency at which the amplitude fluctuates is the beat frequency, which is equal to the difference in frequency of the combining waves, $\size {f_1 - f_2}$.

Correction

It should say:

The frequency at which the amplitude fluctuates is the beat frequency, which is equal to half the difference in frequency of the combining waves, $\dfrac {\size {f_1 - f_2} } 2$.

This is demonstrated in Frequency of Beats.

Sources

• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): beats
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): beats