~~The frequency changes by 10% as a sound source approaches a stationary observer with constant speed Vs What would - Physics - Waves

Question

~~The frequency changes by 10% as a sound source approaches a
stationary observer with constant speed Vs What would be the %
change in the frequency as the source recedes the observer with
same speed (Vs < V) ? 1) 10 5% 2) 8 5% 3) 4 5% 4) 1 5%

Vara · Accepted Answer

Case I: Source approaches a stationary observerf'=vv-vsff'f=vv-vsf'f-1=vv-vs-1f'-ff=vsv-vs0
1=vsv-vsvs=0 1v-0 1vs1 1vs=0
1vv=11vsCase II: Source recedes the stationary observerf'=vv+vsff'f=vv+vsf'f-1=vv+vs-1f'-ff=-vsv+vs            =-vs11vs+vs            =-8
5%Here, - sign indicates decrease in frequency
Ans: Option - (2)

~~The frequency changes by 10% as a sound source approaches a stationary observer with constant speed Vs. What would be the % change in the frequency as the source recedes the observer with same speed (Vs < V) ? 1) 10.5% 2) 8.5% 3) 4.5% 4) 1.5%