Measuring Wave Velocity

Measuring Wave Velocity

1. Calculating the speed of sound in air Method 1: Using an echo 1) Measure the distance from the source of the sound to the reflecting surface (the wall). 2) Measure the time interval, with a stopwatch, between the original sound being produced and the echo being heard.

   • Repeating the experiment a number of times over a range of distances will allow you to obtain accurate and precise results

2. Method 2: Using two microphones and an oscilloscope 1) Set up the microphones one in front of the other at different distances in a straight line from a loud speaker 2) Set the frequency of the sound from the loudspeaker to a known, audible value. 3) Display the two waveforms on the oscilloscope. Measure the distance between the microphones. 4) Move the microphones apart so that the wavefroms move apart by 1 wavelength. 5) Calculate the speed of sound.

3. Calculating the speed of ripples on the surfaces You can work out the speed of ripples using a ripple tank and a strobe light