Question

The frequency of the fundamental note in a wire stretched under tension $T$ is $f$. If the tension is increased to $25 \,T$, then the frequency of the fundamental note will be

• A. 25 f
• B. 5 f
• C. 10 f
• D. f

Answer 1

Answer: (B)

5 f

Answer 2

The fundamental frequency $f=\frac{1}{2 L} \sqrt{\frac{T}{m}}$ $\therefore \frac{f'}{f}=\sqrt{\frac{T'}{T}}$ $=\sqrt{\frac{25 T}{T}}=5$ or $f'=5\, f$