Question

The speed of sound in air is $v$. Both the source and observer are moving towards each other with equal speed $u$. The speed of wind is$w$ from source to observer. Then, the ratio $\left(\frac{f}{f_0}\right)$ of the apparent frequency to the actual frequency is given by

• A. $\frac{v+u}{v-u}$
• B. $\frac{v+w+u}{v+w-u}$
• C. $\frac{v+w+u}{v-w-u}$
• D. $\frac{v-w+u}{v-w-u}$

Answer 1

The correct option is C $\frac{v+w+u}{v-w-u}$

$\begin{array}{c}f=\left(\frac{v+u+w}{v-u+w}\right)f_0\\ \Rightarrow \frac{f}{f_0}=\left(\frac{v+u+w}{v-u+w}\right)\\ Hence,\\ optionCiscorrectanswer.\end{array}$