I remember a very similar experiment when I was at school where the teacher had the class clap in cadence with the echo, and by measuring the clapping frequency and distance to the wall we got a surprisingly accurate estimate of the speed of sound.
I remember a very similar experiment when I was at school where the teacher had the class clap in cadence with the echo, and by measuring the clapping frequency and distance to the wall we got a surprisingly accurate estimate of the speed of sound.