Answer:
516.13 m/s
263.33 Hz
Explanation:
Given:
length of the pipe closed at one end, L = 0.490 m
Third harmonic Frequency, f= 790 Hz
Wavelength of the third Harmonic is given by:
[tex]\lambda = \frac {4}{3}L[/tex]
speed of sound in unknown gas can be calculated as follows:
[tex] v= f\lambda\\ \Rightarrow v= f(\frac {4}{3}L)[/tex]
Substitute the values:
[tex]v= (790)\frac{4}{3}(0.490) = 516.13 m/s[/tex]
Fundamental frequency is given by:
[tex]f_1=\frac{v}{4L}[/tex]
Substitute the values:
[tex]f_1=\frac{516.13}{4\times 0.490}= 263.33 Hz[/tex]
