A piston fitted in cylindrical pipe is pulled as shown in the figure. A tuning fork is sounded at open end and loudest sound is heard at open length $13 ext{ cm}$, $41 ext{ cm}$ and $69 ext{ cm}$. The frequency of tuning fork, if velocity of sound is $350 ext{ ms}^{-1}$, is [DUMET 2011]

Question

A piston fitted in cylindrical pipe is pulled as shown in the figure. A tuning fork is sounded at open end and loudest sound is heard at open length $13	ext{ cm}$, $41	ext{ cm}$ and $69	ext{ cm}$. The frequency of tuning fork, if velocity of sound is $350	ext{ ms}^{-1}$, is [DUMET 2011]

Aicharya · Accepted Answer

In a closed organ pipe in which length of air-column can be increased or decreased. The first resonance occurs at $\lambda / 4$ and second resonance occurs at $3\lambda / 4$.

A piston fitted in cylindrical pipe is pulled as shown in the figure. A tuning fork is sounded at open end…

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