For sound waves, if the number of nodes for the $5^{th}$ harmonic of an open-ended pipe is $n$ and that for the $9^{th}$ harmonic of the same pipe with one of its ends closed is $m$, the ratio $\frac{n}{m}$ is :

$A$ source of frequency $340 \,Hz$ is kept above a vertical cylindrical tube closed at the lower end. The length of the tube is $120 \,cm$. Water is slowly poured in just enough to produce resonance. Then, the minimum height (velocity of sound $= 340 \,m/s$) of the water level in the tube for that resonance is (in $\,m$)

$Assertion :$ The fundamental frequency of an open organ pipe increases as the temperature is increased.
$Reason :$ As the temperature increases,the velocity of sound increases more rapidly than the length of the pipe.

$A$ tuning fork of frequency $256\, Hz$ resonates with a closed organ pipe of length $25.4\, cm$. If the length of the pipe is increased by $2\, mm$,the number of beats per second will be:

$A$ closed organ pipe and an open pipe of the same length produce $4$ beats when they are set into vibrations simultaneously. If the length of each of them were twice their initial lengths,the number of beats produced will be

The end correction for the vibrations of air column in a tube of circular cross-section will be more if the tube is