TRY THIS Beat the opening of the middle pipe with the palm of your hand. Listen for the different arrivals, the duration of each sound and the pitch (frequency) coming from the 2 other pipes.
WHAT IS HAPPENING The sound created in the middle pipe is split: one portion travels the 72m-long left section; the other travels the 12m-long right section. The sounds that come out are distorted and extended because parts of the input travel straight through, while other parts bounce (echo) off the pipe walls to emerge slightly later. This effect called reverberation or multiple echoes, makes the output sounds last longer than the input pulse. The speed of sound in air is about 330ms–1. Since the ratio of the pipes' lengths is 72:12 = 6:1, the travel times ratio is also 6:1. Can you detect this? |
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PS–52 
