If the end correction of an open pipe is $0.8 \,cm$, then the inner radius of that pipe is

$A$ student determines the velocity of sound with the help of a closed organ pipe. If the observed length for the fundamental frequency is $24.7 \, cm$,the length for the third harmonic will be .... $cm$.

$A$ glass tube $1.5 \ m$ long and open at both ends is immersed vertically in a water tank completely. $A$ tuning fork of $660 \ Hz$ is vibrated and kept at the upper end of the tube,and the tube is gradually raised out of the water. Taking the velocity of sound in air as $330 \ m/s$,find the total number of resonances heard before the tube comes out of the water.

$A$ whistle whose air column is open at both ends has a fundamental frequency of $5100 \ Hz$. If the speed of sound in air is $340 \ ms^{-1}$, the length of the whistle, in $cm$, is

An open organ pipe of length $l$ is sounded together with another organ pipe of length $l + x$ in their fundamental tones $(x << l)$. The beat frequency heard will be (speed of sound is $v$):

$A$ closed organ pipe $150 \ cm$ long gives $7$ beats per second with an open organ pipe of length $350 \ cm$,both vibrating in fundamental mode. The velocity of sound is . . . . . . $m/s$.