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JEE Main202126 Aug 2021Morning ShiftPhysicsWaves and SoundActual

A source and a detector move away from each other in absence of wind with a speed of 20 m s - 1 , 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 the speed of sound in the air 340 m s - 1 will be _____ Hz .

Correct answer

0

Step-by-step solution

The formula of apparent frequency in terms of velocity of the source and observer is, f ′ = f v − v 0 v + v s , now put the values which are given in the question, ⇒ 1800 = f 340 − 20 340 + 20 ⇒ f = 1800 × 360 320   Hz ⇒ f = 2025   Hz

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