$A$ pipe $30 \, cm$ long is open at both ends. Which harmonic mode of the pipe resonates with a $1.1 \, kHz$ source? (Speed of sound in air $= 330 \, m/s$)

$A$ wire of length $L$ and linear density $m$ is stretched between two rigid supports with tension $T$. It is observed that the wire resonates in the $P^{th}$ harmonic at a frequency of $320 \text{ Hz}$ and resonates again at the next higher frequency of $400 \text{ Hz}$ in two successive modes. The value of $P$ is

$A$ pipe $17 \, cm$ long is closed at one end. Which harmonic mode of the pipe resonates with a $1.5 \, kHz$ source? (Speed of sound in air $= 340 \, m \, s^{-1}$)

Two open organ pipes of lengths $50 \,cm$ and $51 \,cm$ are totally immersed in a medium. They are found to give $40$ beats in $10 \,s$ when each is sounding at its fundamental note. The speed of sound in this medium is (in $\,ms^{-1}$)

An organ pipe closed at one end has a fundamental frequency of $1500 \ Hz$. The maximum number of overtones generated by this pipe which a normal person can hear is:

The difference between the fundamental frequencies of an open pipe and a closed pipe of the same length is $100 \ Hz$. The difference between the frequencies of the second harmonic of the open pipe and the third harmonic of the closed pipe is: (in $Hz$)