Singing Rod

This is a demonstration for resonance and standing waves.

Our singing rods happen to be leftover bits from machining another demo. However, many education stores sell them and Arbor Scientific has an interesting link that talks about the Singing Rod here.

1. Hold the aluminum rod firmly with two (or three) fingers of one hand.
2. cover the thumb and forefinger of your other hand with crushed rosin.
3. Slide and pinch your 'sticky' fingers from the center of the rod to one of its ends.
4. Repeat and observe the resonance.

Please note this can get uncomfortably loud, especially for young, sensitive ears!

Hold the rod at different nodal points to get resonance at different frequencies.