A sound wave travels at a speed of 339 ms–1. If its wavelength is 1.5 cm, what is the frequency of the wave? Will it be audible?
Solution and Explanation
Sound Speed (v): 339 m/s
Sound Wavelength (\(λ\)): 1.5 cm = 0.015 m
The formula relating speed, wavelength, and frequency is \(v=λ×f.\)
\(f=\frac{v}{λ}=\frac{339}{0.015}\)=22600Hz
The frequency of audible sound for humans typically ranges from 20 Hz to 20,000 Hz. Given the sound frequency of 22,600 Hz, it falls outside the audible range, indicating that it is not audible to human ears.
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Concepts Used:
Sound
Sound is a vibration that propagates the mechanical wave of displacement and pressure, through a medium can be of any matter. In other words, the sound is the thin line between Music sound and Noise.
Types of Sounds:
Sound can be divided into two types depending on its frequency. The following are:-
Infrasonic Waves:
- Infrasonic waves have a frequency lower than 20 Hz. Since it is below the human hearing range, it is inaudible to humans.
- However, several other living organisms use these waves to communicate, whales, sharks, elephants, hippopotamus, etc. these waves are also used in the scientific field, it is used to study upcoming earthquakes, volcanic eruptions, human heart rates, rock formation stages, etc.
Ultrasonic waves:
- Ultrasonic waves have a frequency higher than 20 kHz. Since it is above the human hearing range, it is inaudible to humans.
- These waves are used in the scientific field, it is used to study human heart rates, to take sonograms, navigation of directions, imaging things, uniform sample mixing, communication, testing of samples, etc.