Easy INTEGER +4 / -1 PYQ · JEE Mains 2021

A source and a detector move away from each other in absence of wind with a speed of 20 m/s with respect to the ground. If the detector detects a frequency of 1800 Hz of the sound coming from the source, then the original frequency of source considering speed of sound in air 340 m/s will be ............... Hz.

Answer (integer) 2025

Solution

Image<br><br>$f' = f\left( {{{C - {V_0}} \over {C + {V_s}}}} \right)$<br><br>$\Rightarrow$ $1800 = f\left( {{{340 - 20} \over {340 + 20}}} \right)$<br><br>f = 2025 Hz

About this question

Subject: Physics · Chapter: Waves · Topic: Wave Motion and Types

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