3034 Apparatus to measure acoustic waves' velocity in air

This equipment can measure the speed of sound measuring the displacement Δx between the loudspeaker and microphone to ensure that between the two waves, initially in phase, there is a delay time equal to the period of oscillation T or a multiple of T. The speaker is connected to the function generator that produces a sinusoidal signal of known frequency displayed on channel 1 of the oscilloscope.
The output signal from the microphone receiver is instead displayed on the channel 2 of the oscilloscope. Changing the distance between the loudspeaker and microphone the two signals could be initially in phase. In practice, this is possible keeping the speaker fixed and moving the microphone, or vice-versa. 

Using the bench you can measure the distance λ (wave length) at which the delay is a period T.

1 Bench 50 cm
2 Holders
1 Loudspeaker
1 Microphone with amplifier
2 Leads
2 BNC Leads

1 Acoustic signals generator code 5718
1 Double traces oscilloscope code 5195