A 20.0 cm long organ pipe is filled with air and is open at one end and closed at the other. The speed of sound in air at 0°C is 331 m/s. What is the frequency of the fundamental mode?
A) 414 Hz
B) 387 Hz
C) 345 Hz
D) 302 Hz
E) 295 Hz

Question

Quizplus · Accepted Answer

The fundamental frequency for a pipe open at one end and closed at the other is given by $f = \frac{v}{4L}$, where $v$ is the speed of sound in air (331 m/s at 0°C) and $L$ is the length of the pipe (0.20 m). Plugging in the values, $f = \frac{331}{4 \times 0.20} = 414.375$ Hz, which rounds to 414 Hz, making option A correct.

A 200 Cm Long Organ Pipe Is Filled with Air and and Is