A tunning fork of frequency 340 Hz resonates in the fundamental mode with an air column of length 125 cm in a cylindrical tube closed at one end. When water is slowly poured in it, the minimum height of water required for observing resonance once again is ___________ cm.
(Velocity of sound in air is 340 ms$-$1)
Answer (integer)
50
Solution
<p>Given $340 = {n \over {4 \times 125}}v$</p>
<p>$\Rightarrow n = 5$</p>
<p>So $\lambda = 100$ cm</p>
<p>So minimum height is ${\lambda \over 2} = 50$ cm</p>
About this question
Subject: Physics · Chapter: Waves · Topic: Wave Motion and Types
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