A bat emitting an ultrasonic wave of frequency 4.5 × 10^4 ~Hz at...

A bat emitting an ultrasonic wave of frequency

4.5 \times 10^4 \mathrm{~Hz}

at speed of

6 \mathrm{~m} / \mathrm{s}

between two parallel walls. The two frequencies heared by the bat will be A bat emitting an ultrasonic wave of frequency 4.5 × 10^4 ~Hz at speed of 6 ~m / s between two parallel walls. The two

A bat emitting an ultrasonic wave of frequency 4.5 × 10^4 ~Hz at speed of 6 ~m / s between two parallel walls. The two

Options

A $4.67 \times 10^4 \mathrm{~Hz}, 4.34 \times 10^4 \mathrm{~Hz}$
B $4.34 \times 10^4 \mathrm{~Hz}, 4.67 \times 10^4 \mathrm{~Hz}$
C $4.5 \times 10^4 \mathrm{~Hz}, 5.4 \times 10^4 \mathrm{~Hz}$
D $4.67 \times 10^3 \mathrm{~Hz}, 4.34 \times 10^4 \mathrm{~Hz}$

Correct answer

B. $4.34 \times 10^4 \mathrm{~Hz}, 4.67 \times 10^4 \mathrm{~Hz}$

Step-by-step solution

Frequency received by bat after reflection from wall (1).

\begin{aligned} t_2 & =f\left[\frac{v-u}{v+u}\right] \\ & =4.5 \times 10^4\left[\frac{330-6}{300+6}\right] \\ & =4.34 \times 10^4 \mathrm{~Hz}\end{aligned}

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