question_answer

A longitudinal wave of wavelength 1 cm travels in air with a speed of \[\text{3}00\text{ m}{{\text{s}}^{-\text{1}}}.\]Can this wave be heard by a normal human being?

Answer:

Given, \[\lambda =1cm=\frac{1}{100}m\] \[v=300\text{ }m{{s}^{1}}\] \[n=?\] We know, \[V=n\lambda \] \[\Rightarrow \]\[n=\frac{V}{\lambda }\] \[=\frac{300}{{}^{1}/{}_{100}}=30,000Hz\] Therefore, it can't be heard. Since for the normal human being to hear the audibility should be between 20 Hz to 20,000 Hz.