wave_mechanics organ_pipe_vibration_of_air_column Question 11

Question: If the velocity of sound in air is 336 m/s. The maximum length of a closed pipe that would produce a just audible sound will be

[KCET 2001]

Options:

A) 3.2 cm

B) 4.2 m

C) 4.2 cm

D) 3.2 m

Show Answer

Answer:

Correct Answer: B

Solution:

Minimum audible frequency = 20 $ Hz $ .

               $ \Rightarrow  $  $  \frac{v}{4l}=20\Rightarrow l=\frac{336}{4\times 20}=4.2 $ 

$ m $