Question

A longitudinal standing wave can be created in a long, thin aluminum rod by stroking the rod with very dry fingers. This is often done as a physics demonstration, creating a high-pitched, very annoying whine. From a wave perspective, the standing wave is equivalent to a sound standing wave in an open-open tube. In particular, both ends of the rod are anti-nodes. (Figure 1) Part A What is the fundamental frequency of a 2.20 -long aluminum rod? The speed of sound in aluminum is 6420 .

Answer 1

Wavelength = 2* Length
So, λ = 1 * 2.2 = 4.4 m

fo = v / λ = 6420 /4.4 = 1459.091 Hz