PR-78
Photogates allow for extremely precise measurements of high-speed or short-duration events. Typical applications within physics experiments include; for studying free fall acceleration, air track collisions, period of a pendulum, velocity of a rolling object, among other things.
These include a pair of photo gates which are housed in tough moulded cases giving them excellent durability.
A photogate consists of a light source consisting of a narrow infra-red beam providing the timing signals, and a light detector.
The photo gates can be connected by 4 mm sockets to the timer and the power supplies.
As long as the beam strikes the detector, the signal to the timer indicates that the beam is unblocked.
When an object moves through and blocks the infrared beam of light between the source in one arm and the detector on the opposite arm, an LED on top of the gate gets illuminated and the signal to the timer changes.
The timer has several options for timing the photogate signals. The options include Gate, Pulse, and Pendulum modes, allowing you to measure the velocity of an object as it passes through the photogate or between two photogates, or to measure the period of a pendulum. There is also a start/stop button that lets you use the timer as an electronic stopwatch.