Ultrasonic experiments 2: Standing wave

### Ultrasonic experiments 2: Standing waves ###

I have developed a series of experiments with ultrasound waves that can be done by students in upper-level physics lessons. The experiments will be presented in arbitrary order in the future.

These experiments include:
1: reflection and absorption of ultrasonic waves
2: standing waves
3: interference with two transmitters
4: the double-slit experiment
5: the effect of a semipermeable plate
6: the Michelson interferometer
7: the Mach-Zehnder interferometer
8: the distance measurement with an Arduino

#### COMPONENTS ####

curcuit_board_mount: For the curcuit i used a board of 5cm x 7cm, which is sufficent for the ultrasonic sound generator. I chose a standard curcuit with the NE555. The mount can be pr