Question

The string of a sonometer is divided into two parts with the help of wedge. The total length of the string is $1m$ and the two parts differ in length by $2mm$. When sounded together, they produce two beats. The frequencies of the notes emitted by the two parts are

• A. $499$ and $497$
• B. $501$ and $503$
• C. $501$ and $499$
• D. none of these

Answer 1

The correct option is C $501$ and $499$

$\frac{v}{49.9}-\frac{v}{51}=2or0.2v=2\times 50\times 49.9$
$orv=50.1\times 499$
$f_1=\frac{50.1\times 499}{5.1}=499Hz{f}_2=501Hz$