Question

A stretched string of length $1m$ fixed at both ends, having a mass of $5\times {10}^{-4}kg$ is under a tension of $20N$. It is plucked at a point situated at $200cm$ from one end. The stretched string would vibrate with a frequency of

• A. $200Hz$
• B. $100Hz$
• C. $250Hz$
• D. $256Hz$

Answer 1

The correct option is A $200Hz$

$\begin{array}{c}v=\frac{2}{2l}\sqrt{\frac{T\times l}{M}}\\ or,\sqrt{\frac{T}{Ml}}=\sqrt{\frac{20}{5\times 10-4\times l}}\\ =\sqrt{4\times {10}^4}Hz=200Hz\end{array}$