Question

A cylinderical tube open at both ends, has a fundamental frequency f in air. The tube is dipped vertically in water so that half of it is in water. The fundamental frequency of air column is now
A. n/2
B. n
C. 2n
D. 4n

Answer 1

Correct Answer - B
`n_1=n " " l_2=l/2`
`n_2/n_1 = (v)/(4l//2) (2l)/(v) = 1`
`n_2 = n_1 =n`
Since when the tube is dipped in water it acts as open at one end closed to the other end.