# A source of sound A emitting waves of frequency 1800 Hz is falling towards ground with a terminal speed v. The observer B on the ground directly beneath the source receives waves of frequency 2150 Hz. The source A receives waves, reflected from ground of frequency nearly: (Speed of sound = 343 m/s)

Question:

A source of sound A emitting waves of frequency 1800 $\mathrm{Hz}$ is falling towards ground with a terminal speed $\mathrm{v}$. The observer B on the ground directly beneath the source receives waves of frequency $2150 \mathrm{~Hz}$. The source $\mathrm{A}$ receives waves, reflected from ground of frequency nearly: (Speed of sound $=343 \mathrm{~m} / \mathrm{s}$ )

1. $2150 \mathrm{~Hz}$

2. $2500 \mathrm{~Hz}$

3. $1800 \mathrm{~Hz}$

4. $2400 \mathrm{~Hz}$

Correct Option: 2

Solution:

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