Question
A stretched string resonates with tuning fork frequency $512\; Hz$ when length of the string is $0.5\; m$. The length of the string required to vibrate resonantly with a tuning fork of frequency $256 \;Hz$ would be .......... $m$
✓
Answer
$f=\frac{1}{2 l}\left[\frac{T}{\mu}\right]^{\frac{1}{2}}$
When $f$ is halved, the length is doubled.
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