"Joe Here" wrote in message
...

A 12 Volt bulb (automotive/RV type) running on AC is being turned on
and off 120 times per second (60 Hertz). Although way too fast for
general themometers, it's also experiencing a temperature change 120
times per second. By design, the bulb may be designed to withstand the
vibration associated with auto/RV applications, but not the super
rapid temperature changes.

The thermal lag of an incandescent bulb is way too slow for there to be any
significant amount of temperature variation on a per cycle basis.

Rod