A vehicle with a horn of frequency n, is moving with a velocity of 30 ms -1 in a direction perendicular to the straight line joining the observer and the vehicle. The observer receives the sound to have a frequency n+n1. Then (if the sound velocity in air is 300 ms -1 )

Question

A vehicle with a horn of frequency n, is moving with a velocity of 30 ms -1 in a direction perendicular to the straight line joining the observer and the vehicle. The observer receives the sound to have a frequency n+n1. Then (if the sound velocity in air is 300 ms -1 ) (A)  n1=10n  (B)  n1=0  (C)  n1=0.1 n  (D)  n1=-0.1n

Tardigrade Admin · Accepted Answer

When velocity of source is perpendicular to the line joining observer and source, then there is no Doppler's effect, so n1=0.

Q. A vehicle with a horn of frequency $n$ , is moving with a velocity of $30 m s^{- 1}$ in a direction perendicular to the straight line joining the observer and the vehicle. The observer receives the sound to have a frequency $n + n_{1}$ . Then (if the sound velocity in air is $300 m s^{- 1}$ )

$n_{1} = 10 n$

$n_{1} = 0$

$n_{1} = 0.1 n$

$n_{1} = - 0.1 n$

When velocity of source is perpendicular to the line joining observer and source, then there is no Doppler's effect, so $n_{1} = 0$ .

Q. A vehicle with a horn of frequency n, is moving with a velocity of 30ms−1 in a direction perendicular to the straight line joining the observer and the vehicle. The observer receives the sound to have a frequency n+n1​. Then (if the sound velocity in air is 300ms−1 )

n1​=10n

n1​=0

n1​=0.1n

n1​=−0.1n