2006-11-19 05:43:38 · 13 answers · asked by briancousins@btinternet.com 1 in Science & Mathematics ➔ Physics
when it's cold :)
2006-11-19 05:51:56 · answer #1 · answered by Anonymous · 0⤊ 0⤋
No noticable mass change at any point! The idea of the electrons adding mass when switched on wouldn't be the case as the number of electrons would remain the same just that they would now be moving through the fillament. A new bulb may way a little more since the element actually radiates a certain amount of its material as it burns, although I doubt it ever leaves the confines of the bulb so this wouldn't be the case. Again if everything remained intacked and didn't explode the burnt out bulb with air would indeed be heavier than on i n a vacum(very verysmall amount!!)
2006-11-20 09:35:04 · answer #2 · answered by acontractornow 2 · 0⤊ 0⤋
The mass of a lightbulb does not change regardless of when it's on or off.
When the bulb is on, there are electrons moving through the filament and connections. Yes the electrons have mass, but all they are doing is shuffling about, as one enters the 'beginning' of the filament one will leave the 'end' but with less energy. There is no net gain or loss of electrons and therefore no net gain or loss of mass.
Photons do have mass (although they have no 'rest mass') they are produced when the atoms in the filament are excited by the passing electrons and emit an electromagnetic wave.
Bear in mind, energy and mass are essentially the same!
2006-11-19 18:12:27 · answer #3 · answered by Andrew H 2 · 0⤊ 0⤋
A light bulb is at its heaviest when it weighs the most.
2006-11-19 13:46:24 · answer #4 · answered by Joy 2 · 1⤊ 0⤋
If the bulb has to weigh more than what it was, there should be more upward tension against gravity. If gas is there then it will be heated up and pressure increases and consequent upward thurst increases and we will feel less weighter than before and if it is vacuum then there wont be any difference. So when is cold we will feel much weighter. The effect of radiation on bulb is minimal.
2006-11-19 14:13:37 · answer #5 · answered by haris 1 · 0⤊ 0⤋
When its on.
This is the time when electrons are flowing through it (and electrons have mass). Otherwise, a sealed light bulb can be considered as a 'closed system' (I'm not counting photons as they have no mass).
As the famous video clip of the Mayor of Scarborough advertising how great the place is. When he finished he said something to the words "If you believe that old load of codswallop...."
2006-11-19 14:51:07 · answer #6 · answered by Bill N 3 · 0⤊ 0⤋
When it's broken. The gasses in the bulb are slightly less dense than air, and so when the air comes in, it is heavier than the gasses that were in it. When youweight the broken pieces of the bulb, they include the air.
19 NOV 06, 1856 hrs, GMT.
2006-11-19 13:52:28 · answer #7 · answered by cdf-rom 7 · 0⤊ 0⤋
Not sure of that one....but, did you know that in a fire, the light bulbs will melt and tilt toward the heat source. Fascinating, useless trivia!
2006-11-19 13:52:58 · answer #8 · answered by st pete rn 3 · 0⤊ 0⤋
When it's been on for about 2 hours. You try holding one when it's on !
2006-11-20 08:24:57 · answer #9 · answered by Timbo 3 · 0⤊ 0⤋
when the bulb is new. because when the filament is blew out it will be lighter.
2006-11-19 13:52:26 · answer #10 · answered by e1-ferrari 2 · 0⤊ 0⤋
When it's off. It's not so light see?
2006-11-19 13:52:38 · answer #11 · answered by Anonymous · 0⤊ 0⤋