Ultrasonic experiments 5: Semipermeable plate

### Ultrasonic experiments 5: the effect of a semipermeable plate ### 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-slits 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 for the generator with the NE555. The electrical circuit I have shown in a pdf file. The mount can be printed without a support. mount for parallel horns: the mount for the transmitter horn parallel to the reciever horn. Support is not necessary. parallel horn: Left side: transmitter, right side: reciever, support is not necessary. base: For this part i used the excellent work of jandetlefsen and his thing http://www.thingiverse.com/thing:1412135. I could not find anything more suitable nor could I develop something better myself. Support is not necessary nut M3 and nut M3 2x: generic nuts for M3 for the 20x20 aluminium profile system. mount for reflection plate the mount for the 150x150 mm aluminium plate semipermeable plate : This semi-permeable plate consists of squares with a side length of 7 mm (ie an area of ​​50mm²) with a square cutout with a side length of 5mm (ie an area of ​​25mm²). pointer : For an exact determination of the wavelength this pointer is helpful. #### Things you need more #### Aluminium profiles : for this experiment i recommend one 50cm long profiles Screws and nuts: a lot of M3 screws for mounting on the profiles (M3 x 10mm, M3 x 16mm). Some M5 screws and nuts for the bases. Aluminium plates: i recommend a plate of 150mm x 150mm with a thickness of 2mm. #### Results of the experiment #### f you slowly move the reflection plate towards the semipermeable plate, you get about every 4mm (half wavelength!) an interference maximum.