Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEET2019PhysicsWaves and SoundActual

Two sources of sound S₁ and S₂ are moving towards and away from a stationary observer with same speed respectively. Observer detects 3 beats per second. Find the speed of sources (approximately). Given, v₁=v₂=500 ~Hz , speed of air =330 ~m ~s ⁻¹

Options

  1. A1 ~m ~s ⁻¹
  2. B2 ~m ~s ⁻¹
  3. C3 ~m ~s ⁻¹
  4. D4 ~m ~s ⁻¹

Correct answer

A. 1 ~m ~s ⁻¹

Step-by-step solution

v₁=500 ~Hz , v₂=500 ~Hz S₁ O bserver S₂ Beats frequency =3 beats sec ⁻¹v₁= ( 330 330-v ) 500, v₂= ( 330 330+v ) 500 Beats = (v₁-v₂ ) aligned & 3= ( 330 330-v ) 500- ( 330 330+v ) 500 & 3= 500 330^2-v^2 2 v 330 ( v^2< < 330^2 ) & 3= 500 330 2 v 330^2 & v= 3 330 2 500 v=0.99 ~m ~s ⁻¹=1 ~m ~s ⁻¹ approx aligned

Practice Waves and Sound on Quantrex Academy →

More from Waves and Sound

For the given wave equation y = 10 ( x 4 + t 2 ) , the CORRECT statement is ( where x is in metre and time t is in second.) 2026The source is emitting sound of frequency 'n'. A source and a listener both are moving towards each other with a speed equal to ( V 3 ) , where V is the speed of sound. The frequen 2026Two uniform strings X and Y made of same material made to vibrate under same tension. If the second overtone of string X is equal to the third overtone of string Y and the radius o 2026A simple harmonic progressive wave is represented as Y = 0.04 (2t - 0.02x) m. At a given instant of time, the phase difference between two particles 10 m apart is (in radian) 2026Two waves having same amplitude A , angular frequency and propagation constant k , traveling in opposite directions, have a phase difference of 60^ . If they interfere with each ot 2026Identify the CORRECT statement on beats (A) The amplitude of beats is always constant. (B) Beats are produced when two waves have the same frequency. (C) Beat frequency is the aver 2026An organ pipe closed at one end produces 5^ th overtone of an air column. It is found that air in the pipe is vibrating with x nodes and y antinodes. The value of x and y is 2026The speed of the transverse wave on the stretched string under tension T₁ is v₁ . If the tension in the string is increased by T₁ , the speed of the transverse wave is v₂ . If is t 2026 Full Waves and Sound list All NEET PYQs