Two sound waves of wavelengths $5 \ m$ and $6 \ m$ produce $30$ beats in $3 \ s$. The velocity of sound is .... $m/s$.

Two tuning forks $A$ and $B$ vibrating simultaneously produce $5$ beats. The frequency of $B$ is $512 \ Hz$. It is observed that if one arm of $A$ is filed,the number of beats increases. The frequency of $A$ is: (in $Hz$)

$A$ tuning fork gives $3$ beats with $50 \ cm$ length of sonometer wire. If the length of the wire is shortened by $1 \ cm$,the number of beats is still the same. The frequency of the fork is (in $Hz$)

$A$ source of unknown frequency gives $4\, \text{beats/s}$ when sounded with a source of known frequency $250\, \text{Hz}.$ The second harmonic of the source of unknown frequency gives $5\, \text{beats/s}$ when sounded with a source of frequency $513\, \text{Hz}.$ The unknown frequency is .... $\text{Hz}$

Two sitar strings $A$ and $B$ playing the note '$Ga$' are slightly out of tune and produce beats of frequency $6 \; Hz$. The tension in the string $A$ is slightly reduced and the beat frequency is found to reduce to $3 \; Hz$. If the original frequency of $A$ is $324 \; Hz$,what is the frequency (in $Hz$) of $B$?

Two sound waves of wavelengths $\lambda_1$ and $\lambda_2$ $(\lambda_2 > \lambda_1)$ produce $n$ beats per second. The speed of sound is: