Bob Dobbs wrote:
Following up on my comments:

Bob Dobbs wrote:
dave wrote:
Incandescent lamps turn on and off 60 times a
second.
Not hardly

More like twice that
Assuming the incandescents are powered by 60 Hz commercial mains,
instead of a DC (photovoltaic/battery) system, the voltage is either full off or
at max twice per cycle and some sinusoidal intermediate value the rest of the
time in between, which is imperceptible due to hysteresis of black body
radiation. (filaments take a small bit of time to start to glow or to go out)

Could see it a mile away with a stroboscope.
A stroboscope doesn't see any further
than its own calibrated pulse will illuminate.

Better to detect type of illumination would be a spectroscope
to determine if the visible spectra is continuous or discontinuous.


Thanks. Two crossings per cycle. Thanks.

The point being missed is that CFLs turn on and off thousands of times a
second, therefore have much less flicker than coal buring Edison lamps.