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

Options

A. `n//2`
B. n
C. 2n
D. 4n

Answer

B

Explanation

When tube is open `n=v/(2l)` where n is a fundamental frequency of open organ pipe in air
When half of tube is dipped vertically in water, it behaves as a closed pipe of length `l/2`, so fundamental frequency n in the case is
`therefore n.=v/(4(l//2))=v/(2l)=n`