NEET UGPhysicsModerateNEET 2025

A pipe open at both ends has a fundamental frequency $f$ in air. The pipe is now dipped vertically in a water drum to half of its length. The fundamental frequency of the air column is now equal to:

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Sol. Fundamental frequency of open pipe (at both ends)

f = \frac{v}{2L}

...(i)
<image_1>
Now immersed in water open pipe behaves as closed pipe.
<image_2>

f' = \frac{v}{4(\frac{L}{2})} = \frac{v}{2L}

...(ii)

f = f'

Source: geekyrakshit/indian-exam-questions / neet2025-code45

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