Q. a segment of wire vibrates with a fundamental frequency of 450 Hz under a tension of 9 kg-wt. then tension at which the fundamental frequency of the same wire becomes 900 Hz is
A) 36 kg-wt
B) 27 kg-wt
C) 18 kg-wt
D) 72 kg-wt
Explanation
(a) Fundamental frequency of wire
$f = \frac{1}{2\pi}\sqrt{\frac{T}{m}}$
Or
$f \propto \sqrt{T}$
Or
$\frac{f_{2}}{f_{1}} = \sqrt{\frac{T_{2}}{T_{1}}}$
Or
$\frac{900}{450} = \sqrt{\frac{T_{2}}{9}}$
Or
$T_{2} = 4 \times 9 = 36\ kg - wt$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.