A pipe of length 85, cm is closed from one end. number of possible natural oscillations of air colum

English

Gujarati

Hindi

14.Waves and Sound

normal

A pipe of length $85\, cm$ is closed from one end. Find the number of possible natural oscillations of air column in the pipe whose frequencies lie below $1250\, Hz$. The velocity of sound in air is $340\, m / s$

A

$12$

B

$8$

C

$6$

D

$4$

Solution

For closed organ pipe,

$f=\frac{(2 n+1) v}{4 l}($ where $, n=0,1,1, \ldots)$

According to question,

$\frac{(2 n+1) v}{4 l}<1250$

$2 n+1 < \frac{1250 \times 4 l}{v}$

$2 n+1 < \frac{1250 \times 4 \times 0.85}{340}$

$\Rightarrow 2 n < 11.5$

$n < 5.75$

So $n=0,1,2,3, \ldots 5$

So, we have $6$ possibilities.

Standard 11

Physics

Share

Similar Questions

A car sounding its horn at $480\,Hz$ moves towards a high wall at a speed of $20\,m/s$. If the speed of sound is $340\,m/s,$ the frequency of the reflected sound heard by the passenger sitting in the car will be the nearest to ….. $Hz$

normal

A string of mass $M$ and length $L$ hangs freely from a fixed point. The velocity of transverse wave along the string at a distance $'x'$ from the free end will be

normal

When two waves of almost equal frequencies $v_1$ and $v_2$ reach at a point simultaneously, the time interval between successive maxima is

normal

The length of an open organ pipe is $0.5\, m$. Calculate the fundamental frequency of the pipe, if the velocity of sound in air be $350\, m/sec$ …. $Hz$

normal

A sound-source is moving in a circle and an observer is outside the circle at $O$ as shown in figure. If the frequencies as heard by the listener are $\nu _1, \nu _2$ and $\nu _3$ when the source is at $A, B$ and $C$ position, respectively, then

normal