Singing Rod Beats
Purpose
Two aluminum rods differing by 2 mm in length produce nearly identical tones that beat at ~3 Hz when struck simultaneously. Students hear the amplitude modulation directly and connect it to the beat frequency equation \(f_{beat} = |f_1 - f_2|\).
Figure 1:
Two aluminum singing rods clamped at their center points (black band markings) on a bench clamp rod. The rods differ by 2 mm in length, producing beats at ~3 Hz when both are struck.
Equipment
- 1