Q. Two vibrating strings of the same material but length 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 the length L with frequency $v_{1}$ and the other with frequency$v2\ $. the ratio $v/v_{2}$is

A) 2
B) 4
C) 8
D) 1
Explanation

(d) Fundamental frequency,
$v = \frac{1}{2l}\sqrt{\frac{T}{m}} = \frac{1}{2l}\sqrt{\frac{T}{\pi r^{2}\rho}}\ $
$or\ \ \ \ v \propto \frac{1}{lr}$
$\therefore\ \frac{v_{1}}{v_{2}} = \frac{l_{2}r_{2}}{l_{1}r_{1}} = \frac{2L \times r}{L \times 2r} = 1$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.

Want more practice?
Practice Waves MCQs