Waves

A glass tube of \(1 \mathrm{~m}\) length is filled with water. The water can be drained out slowly from the bottom of the tube. If vibrating tuning fork of frequency \(500 \mathrm{~Hz}\) is brought at the upper end of the tube then total number of resonances obtained are [Velocity of sound in air is \(320 \mathrm{~ms}^{-1}\)]