Figure below shows boat and river with their respective speeds. S is a source, attached to the boat, that emits sound of wavelength 14.45mm at a speed of 1445m/s w.r.t water. A receiver is kept downstream at rest w.r.t. ground, inside water. The frequency detected by the receiver is:-

Question

Figure below shows boat and river with their respective speeds. S is a source, attached to the boat, that emits sound of wavelength 14.45mm at a speed of 1445m/s w.r.t water. A receiver is kept downstream at rest w.r.t. ground, inside water. The frequency detected by the receiver is:- <img class="img-fluid question-image" alt="Question" src="https://cdn.tardigrade.in/q/nta/p-j9zr0i4lvwojly0o.jpg" /> (A) 100695.9Hz (B) 100556.7Hz (C) 101391.2Hz (D) 100696.9Hz

Tardigrade Admin · Accepted Answer

v=fλ f=105Hz ⇒ Velocity of sound w.r.to ground =1447(m/s) ⇒ fapp=(1447/1447 - 10)× 105 =100695.9Hz

Q. Figure below shows boat and river with their respective speeds. $S$ is a source, attached to the boat, that emits sound of wavelength $14.45 mm$ at a speed of $1445 m / s$ w.r.t water. A receiver is kept downstream at rest w.r.t. ground, inside water. The frequency detected by the receiver is:-

$100695.9 Hz$

$100556.7 Hz$

$101391.2 Hz$

$100696.9 Hz$

$v = f λ$
$f = 1 0^{5} Hz$
$\Rightarrow$ Velocity of sound w.r.to ground
$= 1447 \frac{m}{s}$
$\Rightarrow f_{a pp} = \frac{1447}{1447 - 10} \times 1 0^{5}$
$= 100695.9 Hz$

Q. Figure below shows boat and river with their respective speeds. S is a source, attached to the boat, that emits sound of wavelength 14.45mm at a speed of 1445m/s w.r.t water. A receiver is kept downstream at rest w.r.t. ground, inside water. The frequency detected by the receiver is:-

100695.9Hz

100556.7Hz

101391.2Hz

100696.9Hz