Phil Allison wrote:
"JoRob64"
"Phil Allison"
"Graham."


An incandescent light bulb is a good example, If it lasts 1000
hours when run continuously, its life will be considerably shorter
if run (say) 4 hours a day and the time it is on added up.


** Where ever did you get that nonsense from ??

Some web forum ?

I believe turning the bulbs on and off can induce thermal shock which
causes premature failure.


** ******** it does.

There are many applications where incandescent lamps are turned on
and off constantly and their life span is the same.

The OP's hypothetical example ( don't ya just LOVE them) is typical of
domestic lamp use.

****wit.


.... Phil

No Phil, that is not correct. If he only listens to Rap , its lifespan will
be shortend greatly.
Buffalo