This assignment requires you to measure the speed of sound in air using destructive interference and compare with the result shown in class using constructive interference. In sound speed experiments, the difference between destructive and constructive interference depends on whether you are measuring phase cancellation between two sources (the toilet roll method) or resonance in a standing wave (the water tube method). Please refer to the lab manual for experimental details. Click here to access a tutorial featuring the experiment. A report from the National Physical Laboratory with results of this experiment canbe found here. The alternative measurement using constructive interference is available here.