Hello, I'm JW and in this video - lightbulbs
or more correctly lamps, but everybody calls them lightbulbs
so that's what we'll call them here, and we have two of them here, the older type
incandescent with the tungsten filament inside
bayonet cap here as commonly used in the UK and both of these are 60 watts
and of course both the same size and pretty much look identical
this particular one is from Sainsbury's, you can probably read the writing on the top
and if we take this one and put it in the holder over here
it lights up no problem, perfectly fine
just as you would expect, but the other one is slightly different because
this particular one is not a 240 volt item like the Sainsburys one was
this one is only rated at 110 volts and it still 60 watts
so if we take this and place it in here - bad things might happen so
we'll take this outside and see what happens when it put on 240 volts rather than 110.
now this is fairly obvious, on the left we've got the 60 watt 240 volt bulb
and on the right the 60 watt 110 volt one
and I've wired them so they will both be switched on at the same time
and of course the camera will adjust and do weird things as the
things are switched on but we are comparing the brightness
of the normal one one on the left
to the 110 volt version on the right
and we would expect the one on the right to be considerably brighter
because it's being run at more than twice its rated voltage
so let's switch on and see what happens
so that's the power turned on and as you can see the one on the right
is substantially brighter then the one on the left
No surprise as it's being run it more than double its rated voltage
The camera's adjusting there to the white balance or whatever
and notice that the background is lit exclusively by these two lamps
if its the middle-of-the-night
but it's still daytime, this was recorded at about three o'clock
in the afternoon outside.
So nothing seems to be setting on fire
or exploding so we'll leave this on for a while and see what happens
OK just switched off the power to both of them there and as you can see
the one on the right looks a bit more blackened than the
one on the left, and bearing in mind originally they looked exactly the same
and as the camera adjusts there you can see
the left one is fairly white looking
and the one on the right there is certainly a more greyish blackened colour
so let's just have a closer look at that one
and as you can see a definite tint of greyish blackness inside.
That rather strange object on the bottom there is the reflection of the table it's standing on
So certainly the appearance has changed, so what we'll do it to power them on again
and leave it until something breaks or goes wrong in some other fashion
So as before, power on, and again the camera will adjust
to the different light colour and brightness.
that has been about two minutes now into the test here
and shortly this one is going to do something
so there we go, it just simply stops working.
I'll just turn off power on the other one as well
because the test is now complete
So as you can see the one on the left is still the same white colour
as originally, and the one on the right, now broken,
is very much darker and grey in appearance.
Here are the two lamps and this is the one that still works
the normal 240 volt Sainsburys one there and
this is the 110 volt one and the insides have gone a dark colour because the tungsten filament
has essentially evaporated
and been deposited on the inside of the glass making it
a lot darker than it was to start with
It doesn't work anymore because the filament thinned out
and broken at some point inside
That's what happens if you put a at 110 volt
lamp onto a 240 volt supply - it works for a
reasonable time but of course not for very long then eventually just breaks
so no fire or explosion or flames involved
so until next time, thanks for watching