How does a strobe light work ?
There are two ways to operate a strobe light. In one, the light simply
turns on and off repeatedly. In the other, something repeatedly moves in
front of the light, temporarily blocking it.
In both cases, the flickering effect is too fast for our eyes to see
directly. What we can notice is a change is how an object appears to move.
For the moment that the light is off, we don't see anything when the light
comes back on, a moving object isn't quite in the location we remember. It
makes motion look like a step-by-step process rather than continuous flow.
Measurements as a function of time become easier to do by film.
A strobe light uses a capacitor, which is like a quick charging battery,
when the electrical current comes in and the capacitor has been discharged
it quickly charges up (this is when the light is off) once the capacitor
charges up to a high load and releases the energy it goes to the light
source and causes a flash to occur, this can happen many times per second
causing the flashing effect.
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Update: June 2012