A) 300 Hz, 300 Hz
B) 300 Hz, 308 Hz
C) 308 Hz, 308 Hz
D) 308 Hz, 300 Hz
Correct Answer: D
Solution :
Given \[{{f}_{A}}-{{f}_{B}}=8\] ?. (i) \[{{f}_{A}}=\frac{v}{4l}=\frac{v}{4\times 37.5\times {{10}^{-2}}}\] and \[{{f}_{B}}=\frac{v}{4\times 38.5\times {{10}^{-2}}}\] So, \[\frac{{{f}_{A}}}{{{f}_{B}}}=\frac{38.5}{37.5}\] \[\Rightarrow \] \[{{f}_{A}}=\frac{385{{f}_{B}}}{375}\] ??. (ii) Putting value of f^ in Eq. (i), we get \[\frac{385{{f}_{B}}}{375}-{{f}_{B}}=8\] \[\Rightarrow \] \[10{{f}_{B}}=8\times 375\] \[\therefore \] \[{{f}_{B}}=\frac{8\times 375}{10}=300\,Hz\] Hence, from Eq. (i), we get \[{{f}_{A}}=8+300=308\,Hz\]You need to login to perform this action.
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