A glass tube of $1.0\text{ m}$ length is filled with water. The water can be drained out slowly at the…
A glass tube of $1.0\text{ m}$ length is filled with water. The water can be drained out slowly at the bottom of the tube. If a vibrating tuning fork of frequency $500\text{ Hz}$ is brought at the upper end of the tube and the velocity of sound is $330\text{ ms}^{-1}$, then the total number of resonance obtained will be
4
3
2
1
Solution
Wavelength, $\lambda = \frac{v}{f} = \frac{330}{500} = 0.66\text{ m}$
Length of air column at resonance can be $\frac{\lambda}{4}, \frac{3\lambda}{4}, \frac{5\lambda}{4}$, etc.
or $0.165\text{ m}, 0.495\text{ m}, 0.825\text{ m}, 1.155\text{ m}$, etc.
But length of tube is only $1\text{ m}$. Hence, first three resonances will be obtained.