Question

Velocity of sound is v. Source and observer move towards each other with velocities v_s and v₀ respectively. Wind is blowing with a velocity v_m in the direction opposite to the propagation of sound; n is the pitch of the sound. The apparent pitch of the sound heard by the observer is –

• A. $\left( \frac{v + v_{m} + v_{0}}{v + v_{m} + v_{s}} \right)n$
• B. $\left( \frac{v–v_{m} + v_{0}}{v–v_{m} + v_{s}} \right)n$
• C. $\left( \frac{v + v_{m}–v_{0}}{v–v_{m} + v_{s}} \right)n$
• D. $\left( \frac{v–v_{m} + v_{0}}{v–v_{m}–v_{s}} \right)n$

Answer 1

Answer: (D)

$\left( \frac{v–v_{m} + v_{0}}{v–v_{m}–v_{s}} \right)n$

Answer 2

\ n' = n $\left( \frac { \left( v - v _ { m } \right) + v _ { 0 } } { \left( v - v _ { m } \right) - v _ { s } } \right)$