tube with a movab piston one end and closed at the other When tuning forks are sounded over the open end, the follow ing values for resonant lengths are found . Resonant Lengths (m ) Frequency (H z ) 1 st 2 nd 256 0 . 34 5 1 .018 32 0 0 .278 0 . 81 38 4 0 .231 0 .697 512 0 .276 0 . 613 Plot a graph of the wavelength against period using the above results. From your graph, obtain a value for the speed of sound at the temperature of the experiment. A closed pipe ( stopped at one end ) and an open pipe a e are placed side by side . It is found that the second overtone produced by the c e closed pipe gives the same pitch as the third overtone the open pipe Calculate t ratio lengths . The diagram below is drawn to full scale . Point sources S and S, vibrate in phase . Each source produces waves of wavelength 20 m m and identical a X K - - - Determine the interference e e effect that occurs : along XY , the perpendicular bisector of the interval s , 5 , ; at the point P ; along the interval 5 5