If you set up the ninth harmonic on a string fixed at both ends,its frequency compared to the seventh harmonic is:

The fundamental frequency of a sonometer with a weight of $4\,kg$ is $256\,Hz$. The weight required to produce its octave is .... $kg-wt$

Two vibrating strings of the same material but lengths $L$ and $2L$ have radii $2r$ and $r$ respectively. They are stretched under the same tension. Both the strings vibrate in their fundamental modes,the one of length $L$ with frequency $n_1$ and the other with frequency $n_2$. The ratio $n_1/n_2$ is given by

To increase the frequency of transverse oscillations of a stretched string by $40\%$, the tension must be increased by (in $\%$)

Two uniform stretched steel strings $A$ and $B$ are vibrating under the same tension. The first overtone of $A$ is equal to the second overtone of $B$. If the radius of $A$ is twice that of $B$,then the ratio of the lengths of the strings $l_A/l_B$ is:

The fundamental frequency of a sonometer wire increases by $9 \ Hz$,if its tension is increased by $69 \%$,keeping the length constant. The frequency of the wire is (in $Hz$)