Q. A cylindrical tube, open at both ends, has a fundamental frequency $f_{0}$ in air. The tube Is dipped vertically into water such that half of its length is inside water. The fundamental frequency of the air column now is

A) $3f_{0}/4$
B) $f_{0}$
C) $f_{0}/2$
D) $2f_{0}$
Explanation

(b) $n_{open} = \frac{v}{2l_{open}}$
$n_{closed} = \frac{v}{4l_{closed}} = \frac{v}{4l_{open}/2} = \frac{v}{2l_{open}}$
$\left( As\ l_{closed} = \frac{l_{open}}{2} \right),$ $i.e.$ frequency remains unchanged

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