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
A$2$
B$4$
C$8$
D$1$
IIT 2000, Medium
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D$1$
d (d) Fundamental frequency $n = \frac{1}{{2l}}\sqrt {\frac{T}{{\pi {r^2}\rho }}} $
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