Simple physics experiment with smartphone for online classesEasy measurement of speed and acceleration! !Kindle e-Books for examples using model train :https://www.amazon.com/dp/B08YD15NZXWeb shop in Japan (Low price):https://diracma888.thebase.in/items/25640668Mobile Physics Education Lab (Physics experiments using smartphone): https://sites.google.com/view/diracma888/It is an mobile ultrasonic sensor unit that can be directly connected to an Android smartphone developed based on teaching mater