Echo Tube
Send an echo via pneumatic mail
Call into the pipe and listen to the echo. You can use push buttons to close and open the flaps and change the distance at which the sound reflects. Before the sound wave arrives somewhere it takes some time. When we say something the generated sound transmits it away from us. If it hits an obstacle, it will reflect like a ball from the wall and it can happen that it will return. During a reflection at a great distance the human ear perceives the reflected sound separately from the original one ??“ as an echo. The time delay needed is 0.1 s, which corresponds with a distance of about 17 m because the sound has to travel this distance twice ??“ there and back.
