Two trains A and B are moving in the same direction with velocities 30ms- 1 and 10ms- 1 respectively. B is behind from A and A blows a horn of frequency 450Hz . Then the apparent frequency heard by observer on train B is (speed of sound is 330ms- 1 ):

Question

Two trains A and B are moving in the same direction with velocities 30ms- 1 and 10ms- 1 respectively. B is behind from A and A blows a horn of frequency 450Hz . Then the apparent frequency heard by observer on train B is (speed of sound is 330ms- 1 ): (A) 425Hz (B) 300Hz (C)  text450 Hz (D) 350Hz

Tardigrade Admin · Accepted Answer

<img class="img-fluid question-image" alt="Solution" src="https://cdn.tardigrade.in/q/nta/p-9au2y9k9uiymtfmn.jpg" /> fapp=((V + V0/ V + VS))f=((330 + 10/330 + 30))450⇒ fapp=425Hz

Q. Two trains $A$ and $B$ are moving in the same direction with velocities $30 m s^{- 1}$ and $10 m s^{- 1}$ respectively. $B$ is behind from $A$ and $A$ blows a horn of frequency $450 Hz$ . Then the apparent frequency heard by observer on train $B$ is (speed of sound is $330 m s^{- 1}$ ):

$425 Hz$

$300 Hz$

$450 Hz$

$350 Hz$

$f_{a pp} = (\frac{V + V _{0}}{V + V _{S}}) f = (\frac{330 + 10}{330 + 30}) 450 \Rightarrow f_{a pp} = 425 Hz$

Q. Two trains A and B are moving in the same direction with velocities 30ms−1 and 10ms−1 respectively. B is behind from A and A blows a horn of frequency 450Hz . Then the apparent frequency heard by observer on train B is (speed of sound is 330ms−1 ):

425Hz

300Hz

450 Hz

350Hz