Demos: 1G-05 Free fall measurement of 'g'
A steel ball can be held or released by an electromagnet. Photo electric sensors are connected to timers. The top display shows the time between sensor 1 (the release point) and sensor 2 (the middle sensor). The bottom display shows the time between sensor 1 and 3 (at the bottom). A timer reset is on the back of the timers. The ball release is a red button on the front of the apparatus.