In the fundamental mode,the time required for a sound wave to reach the closed end of a pipe filled with air is $t$ seconds. The frequency of vibration of the air column is:

$A$ 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 . . . . . . $m/s$.

An air column in a closed organ pipe vibrating in unison with a tuning fork produces the second overtone. The vibrating air column has:

The second overtone of an open organ pipe is equal to the first overtone of a closed organ pipe. If the length of the closed organ pipe is $15 \ cm$,the length of the open organ pipe is: (in $cm$)

If the seventh harmonic of a closed organ pipe is in unison with the fourth harmonic of an open organ pipe, then the ratio of the length of the closed pipe to that of the open pipe is:

$A$ cylindrical tube open at both ends has a fundamental frequency $f$ in air. When the tube is dipped vertically in water so that one-third part of the tube is in water,the fundamental frequency of the air column becomes (neglect end correction).