Physics - Sound Wave Question with Solution | TestHub

The tube is closed at one end. So, it will act like a closed organ pipe. The lowest frequency produced in the tube$$\begin{array}{l}l=\frac{\lambda }{4},\lambda =4\\ l=1\mathrm{m}\\ f=84\mathrm{Hz}\\ V=n\lambda =84\times 4\end{array}$$ When wave propagate in air, the velocity Here, $$\begin{array}{l}v=\sqrt{\frac{\gamma p}{\rho }}\\ p=1.0\times 10^5\mathrm{N}/{\mathrm{m}}^2\end{array}$$ $$\begin{array}{rl}\rho & =1.2\mathrm{kg}/{\mathrm{m}}^3\\ V^2& =\frac{\gamma P}{\rho }\\ \gamma & =\frac{{\mathrm{v}}^2\cdot \rho }{\mathrm{P}}\\ & =\frac{(84\times 4{)}^2\times 1.2}{1.0\times 10^5}\\ & =\frac{135472.2}{10^5}=1.354\\ & =1.4\end{array}$$