The standing wave frequencies of an open - closed pipetube are f = mv / 4L The length that caused by mth standing wave mode tobe at 599 Hz is L = mv / 4f substitute values v= 343 m/s at 20oC m= 1 , 3 ,5 .... f= 599 Hz *** The height of the water h = 1.35 m -L ***** h = 1.35m - (mv / 4f) Here m = 3 v= 343 m/s at 20oC f =599 Hz Substitute values f =599 Hz Substitute values