Two coherent sound sources A and B produce a sound of wavelength λ . If at t=0 a detector starts moving with constant velocity v0 from point O along y-direction, then the minimum time, after which it detects the sound of maximum intensity, is (D λ )

Question

Two coherent sound sources A and B produce a sound of wavelength λ . If at t=0 a detector starts moving with constant velocity v0 from point O along y-direction, then the minimum time, after which it detects the sound of maximum intensity, is (D > > λ ) <img class="img-fluid question-image" alt="Question" src="https://cdn.tardigrade.in/q/nta/p-ww2c3qsvehrr.png" /> (A) (√7 D/v0) (B) (D/3 v0) (C) (D/v0) (D) (√7 D/3 v0)

Tardigrade Admin · Accepted Answer

4λ cos θ =3λ cos θ =(3/4) ⇒ tan θ =(y/D) ⇒ y=(√7 D/3) t=(√7 D/3 v0)

Q. Two coherent sound sources $A$ and $B$ produce a sound of wavelength $λ$ . If at $t = 0$ a detector starts moving with constant velocity $v_{0}$ from point $O$ along y-direction, then the minimum time, after which it detects the sound of maximum intensity, is $(D >> λ)$

$\frac{7 D}{v _{0}}$

$\frac{D}{3 v _{0}}$

$\frac{D}{v _{0}}$

$\frac{7 D}{3 v _{0}}$

$4 λ cos θ = 3 λ$
$cos θ = \frac{3}{4}$
$\Rightarrow t an θ = \frac{y}{D}$
$\Rightarrow y = \frac{7 D}{3}$
$t = \frac{7 D}{3 v _{0}}$

Q. Two coherent sound sources A and B produce a sound of wavelength λ . If at t=0 a detector starts moving with constant velocity v0​ from point O along y-direction, then the minimum time, after which it detects the sound of maximum intensity, is (D>>λ)

v0​7​D​

3v0​D​

v0​D​

3v0​7​D​