A train,standing in a station yard,blows a wh | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) The frequency of sound heard by an observer depends on the relative motion between the source and the observer. Since both the train (source) and

Vedclass · Accepted Answer

The frequency of sound as heard by the observer standing on the platform will increase.

Vedclass · Answer

(C) The frequency of sound heard by an observer depends on the relative motion between the source and the observer. Since both the train (source) and the observer are stationary relative to the ground,the frequency remains $400 \, Hz$. Thus,statement $(c)$ is incorrect.The speed of sound in the presence of wind is given by $v' = v + w$,where $v = 340 \, m/s$ is the speed of sound in still air and $w = 10 \, m/s$ is the wind speed. So,$v' = 340 + 10 = 350 \, m/s$. Thus,statement $(b)$ is correct.The wavelength $\lambda$ is given by $\lambda = \frac{v'}{f}$. Since $v'$ increases to $350 \, m/s$ while $f$ remains $400 \, Hz$,the wavelength $\lambda$ increases compared to the case in still air. Thus,statement $(d)$ is correct.

$A$ train,standing in a station yard,blows a whistle of frequency $400 \, Hz$ in still air. The wind starts blowing in the direction from the yard to the station with a speed of $10 \, m/s$. Given that the speed of sound in still air is $340 \, m/s$. Mark the $INCORRECT$ statement:

Similar Questions

$A$ string is stretched so that its length is increased by $\frac{1}{\eta }$ of its original length. The ratio of the fundamental frequency of transverse vibration to that of the fundamental frequency of longitudinal vibration will be

One Mach number is equal to

Which of the following is not a transverse wave?

$A$ big explosion on the moon cannot be heard on the earth because

$A$ tuning fork makes $256$ vibrations per second in air. When the velocity of sound is $330\, m/s$,the wavelength of the tone emitted is ... $m$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module