# NEET Physics Waves Questions Solved

Watch Physics > Waves Videos

A cylindrical tube, open at both ends, has a fundamental frequency f0 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

(1) 3 f0/4

(2) f0

(3) f0/2

(4) 2 f0

(2) ${n}_{\text{open}}=\frac{v}{2{l}_{\text{open}}}$

${n}_{\text{closed}}=\frac{v}{4{l}_{\text{closed}}}=\frac{v}{4{l}_{\text{open}}/2}=\frac{v}{2{l}_{\text{open}}}$

$\left(As\text{\hspace{0.17em}}{l}_{closed}=\frac{{l}_{open}}{2}\right)$, i.e. frequency remains unchanged.

Difficulty Level:

• 14%
• 53%
• 19%
• 16%
Crack NEET with Online Course - Free Trial (Offer Valid Till September 22, 2019)