Advertisements
Advertisements
Question
A person has a hearing range from 20 Hz to 20 kHz. What are the typical wavelengths of sound waves in air corresponding to these two frequencies? Take the speed of sound in air as 344 m s−1.
Advertisements
Solution
Given:
Speed of sound in air = 344 ms−1
Frequencies in the audio range:
V1 = 20 Hz, V2 = 200
v = vλ
λ = Vv
kHz = 20000 Hz,
(i) Case I: When frequency V1 = 20 Hz.
λ1 = `"v"/"V"_1`
= `(344 "ms"^-1)/(20 "Hz")`
= 17.2 m
(ii) Case II: When frequency V2 = 20,000 Hz.
λ2 = `"V"/"V"_2`
= `(344 "ms"^-1)/(20,000 "Hz")`
= 0.0172 m
So, the wavelength of sound waves for both frequencies is 17.2 m and 0.0172 m, respectively.
APPEARS IN
RELATED QUESTIONS
What is the audible range of the average human ear?
What is the range of frequencies associated with infrasound?
Can we hear (a) infrasonic waves (b) ultrasonic waves ?
What name is given to the sound waves of frequency too low for humans to hear ?
What name is given to the sound waves of frequency too high for humans to hear ?
What type of sound waves are produced by a vibrating simple pendulum ?
Choose the infrasonic waves and ultrasonic waves from the following frequencies :
(i) 10,000 Hz
(ii) 30,000 Hz
(iii) 18 Hz
(iv) 50,000 Hz
(v) 10 Hz
What are infrasonic waves ? Name two animals which produce infrasonic waves.
A girl is sitting in the middle of a park of dimension 12 m × 12 m. On the left side of it, there is a building adjoining the park and on the right side of the park, there is a road adjoining the park. A sound is produced on the road by a cracker. Is it possible for the girl to hear the echo of this sound? Explain your answer.
For hearing the loudest ticking sound heard by the ear, find the angle x in Fig.12.4.
