Light bulb question (might be too complex for some of you, experts only)

In summary, this little lamp says that the maximum wattage the lamp can handle is 25 watts. This means that a higher wattage light bulb would not shine very bright, and may even cause the lamp to catch on fire.
  • #1
moe darklight
409
0
ok, I know I always think my questions are going to be dumb, but this time I should really get some credit for how dumb it is. but I can't find the answer on the internet so here goes:

This little lamp I have says "max 25W," does this mean that the maximum output of the lamp is 25W, so a higher W bulb won't shine very bright? or does it mean that a higher W light bulb would cause it to catch fire or something?

... I really know nothing about hardware (yes, a light bulb is hardware to me; you don't even want to know my horror stories from car-fixing class in high-school, my mark was 17% and it was a class I actually showed up to).
 
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  • #2
moe darklight said:
or does it mean that a higher W light bulb would cause it to catch fire or something?

This one.

The "wattage" (power) is the rate at which energy is dissipating from the bulb, mostly in the form of infra red "heat" radiation. A 25 W lamp is not designed to deal with any greater rate of heat output. Melting or at least discoloration would occur.
 
  • #3
hey i guess this wud help
25 watts means that the heat generated across the filament of the bulb is equivalent to 25W, that is due to the current flowing in the filament, which if we take I and R as the resistance of filament gives I^2 * R(also equal to V^2/R) as the energy(or heat). now bulbs r caliberated on the basis of the resistance of filament, so the actual way of measuring the lightning ability shd be resistance but it is not (bcoz of some issues that u know). so R is selected as such that the current it takes from the supply (voltage supply is constant, well almost) does not melt the filament material. therefore a higher wattage lamp has a filament of lesser resistance but is more thick then the lesser wattage one, bcoz the higher wattage bulb has to dissipate more heat, thicker filament has a more surface area to dissipate heat..
so u see, only the filament properties(like resistance n its thickness, length) is the deciding factor for the power rating of the lamp.
but dude i might be wrong, i hav just explained it on basic principles, u need an expert opinion n u atleast had a car fixing class, i still didnt.
n filament never catches fire, it melts n the same 25W bulb ll shine bright when connected to a 440V supply then when it is connected to 110V supply, but it ll melt in the case of 440V supply.. hope u got ur answer
 
  • #4
In my opinion, it is not a matter of "melting the bulb". Melting can in principle occur, and of course your bulb will not handle 1 kW, but it is irrelevant. The bulb has been designed to have an optimal brightness at a given value of the power consumption. Using another power will mainly affect the efficiency of your bulb.
 
  • #5
thanks guys! I guess I'll get that 40W out of there.

ank_gl said:
but dude i might be wrong, i hav just explained it on basic principles, u need an expert opinion n u atleast had a car fixing class, i still didnt.

:rofl: thanks anyways. though this is obviously a question only an expert who has attended several years of electrical-thingy-making classes can answer.
 
  • #6
nah dude, i m a mech engg student n that too in my 3rd year, i m still just a lil sweet kid. not much sweet though

n i m not sure that filament ll melt or what, i haven't ever done it, but i wud like to do it, but again my dad won't allow me to
 
  • #7
moe darklight said:
thanks guys! I guess I'll get that 40W out of there.

Good plan! At best, you'll damage your fixture through discoloration or melting of the cover on it with a higher wattage bulb, and at worst, start a fire. It won't instantly destroy the light unless you do something really extreme like put a 100 W bulb in a 25 W fixture, but it's certainly not something you want to leave on for a long time, and not ever unattended.
 
  • #8
Don't put in a brighter bulb than the fitting or shade specifies. You might burn down your house. I've known it happen.
 
  • #9
though this is obviously a question only an expert who has attended several years of electrical-thingy-making classes can answer.

This is a very basic question, and it could be answered by someone who did well in High School physics. I also know some people who have PhDs but would fumble to answer it. I mention this to show the fallacy of asking for advice from 'experts only', it is up to you to judge the quality of the answers you recieve.
 
  • #10
moe darklight said:
thanks guys! I guess I'll get that 40W out of there.



:rofl: thanks anyways. though this is obviously a question only an expert who has attended several years of electrical-thingy-making classes can answer.

It also helps to have had a couple electrical-thingy-destroying classes. Those are pretty fun electives! :devil:

The other reason not to use a larger power rated bulb is that the life of the bulb will be shortened. The lamp is marked for product liability reasons, however (as described already), not to save you money on bulb replacements.
 
  • #11
Crosson said:
This is a very basic question, and it could be answered by someone who did well in High School physics. I also know some people who have PhDs but would fumble to answer it. I mention this to show the fallacy of asking for advice from 'experts only', it is up to you to judge the quality of the answers you recieve.

:rolleyes: Some people need to replace their sarcasm detectors.
 
  • #12
Moonbear said:
:rolleyes: Some people need to replace their sarcasm detectors.
it's the internet! it ruins all my jokes! :cry: there should be a special sarcasm font.
 
  • #13
FOR CRYIN OUT LOUD. Did no one notice my CORRECT response? POST #2!

SHEESH:grumpy:

Hey Moe. You got that Mission of Burma yet?
 
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  • #14
Chi Meson said:
FOR CRYIN OUT LOUD. Did no one notice my CORRECT response? POST #2!
Yes, but I think some people may have misread it, thinking "it" was the bulb, not the lamp...of course some people call bulbs lamps anyway...
 
  • #15
Humor is lost on the interweb...
 
  • #16
Chi Meson said:
FOR CRYIN OUT LOUD. Did no one notice my CORRECT response? POST #2!

SHEESH:grumpy:

Hey Moe. You got that Mission of Burma yet?

haha, yea thanks.

:approve: it's going to take more than one or two good 80's bands to make up for this:
http://youtube.com/watch?v=ASisLT5XHtg

and there's just no excuse for this:
http://youtube.com/watch?v=c6YGqgLD2As

... though it might still all have been worth it, for this:
 
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  • #17
berkeman said:
It also helps to have had a couple electrical-thingy-destroying classes. Those are pretty fun electives! :devil:

not just electrical, all the DIY= destroy it yourself experiments are cool.
nah humor is not lost, its all so much fun here
 
  • #18
moe darklight said:
haha, yea thanks.

:approve: it's going to take more than one or two good 80's bands to make up for this:
http://youtube.com/watch?v=ASisLT5XHtg

and there's just no excuse for this:
http://youtube.com/watch?v=c6YGqgLD2As

... though it might still all have been worth it, for this:


Here they are. This is them after regrouping. Sound is not the best, and Colin seems to go off key at one point. But this song was out in 1981, and that's when the music of the 90s began.
http://www.youtube.com/watch?v=gzMu6ugTNfA&mode=related&search=
(since this is Moe's thread, and since the OP was insignificant, I think we can go off topic to a previously established discussion.)
 
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  • #19
Chi Meson said:
(since this is Moe's thread, and since the OP was insignificant, I think we can go off topic to a previously established discussion.)

do you REALLY think that we've covered all the intricacies of light-bulb wattage requirements?!

Here they are. This is them after regrouping. Sound is not the best, and Colin seems to go off key at one point. But this song was out in 1981, and that's when the music of the 90s began.
http://www.youtube.com/watch?v=gzMu6...elated&search=

That is pretty 90's sounding, I dig their live show. Most MTV bands suck live now a days; they put them on huge tours so early in their career that they never learn how to put on a proper show.


Probably the best band I've seen live is queens of the stone age, their shows are just kick-ass in a jar.
I saw this band called "throw rag" open for them once and their live show was insane too, watch this if you want to see the greatest washboard solo ever about 2 minutes in:

that poor kid they bring on stage looks really nervous :rofl:. their CD sucks but their live shows are awesome.
 
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  • #20
Chi Meson said:
Here they are. This is them after regrouping. Sound is not the best, and Colin seems to go off key at one point. But this song was out in 1981, and that's when the music of the 90s began.
http://www.youtube.com/watch?v=gzMu6ugTNfA&mode=related&search=
(since this is Moe's thread, and since the OP was insignificant, I think we can go off topic to a previously established discussion.)

hey what happened to the bulb question.. can anyone tell me if i was right or wrong?
everybody here is busy here talking of some video. this is a PHYSICSforum
 
  • #21
The bulb question was answered in post #2. Bulb question is over.

And this is the "General discussion" area in which we can talk about anything we want. As long as the thread starter doesn't mind, a thread may take whatever turn the thread happens to go.

Regarding being right or wrong, I'll tell you: you weren't wrong, but your answer did not answer the question that was asked by the OP.

Also, you were hard to understand; a little too much txt mssg style. Write the whole words, please; that phone pad shorthand makes one look like a schoolboy.
 
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  • #22
Chi Meson said:
Also, you were hard to understand; a little too much txt mssg style. Write the whole words, please; that phone pad shorthand makes one look like a schoolboy.

yeah i got a warning for writing like that. sorry. but hey i m a school boy.
and i just wanted to know whether i was right or wrong. don't get mad on me.
 
  • #23
ank_gl said:
yeah i got a warning for writing like that. sorry. but hey i m a school boy.
and i just wanted to know whether i was right or wrong. don't get mad on me.

Oh I'm not mad at all. There's no problem here. I just believe in direct and truthful answers.:tongue::biggrin::approve::cool:
 
  • #24
i just wanted to explain why it happens. i don't believe in direct(truthful) yes or no type answers. they are for schoolboys.
wait i am also a schoolboy, but still yes or no is not enough.
also i am not trying to say that you are wrong or right. you are of course right. but sorry for being so stupid
 
  • #25
If you are interested in giving detailed answers to other people's questions then go to the https://www.physicsforums.com/forumdisplay.php?s=&daysprune=30&f=153" section. If you do a good job, you might get a shiny medal, plus access to the Homework Helpers forum, which has a jacuzzi and a large fish buffet (fresh daily, but don't go on Tuesday's, or at least stick to the smoked salmon)
 
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  • #26
cheh.. everyone hates me so much
 

1. What is the science behind how a light bulb works?

The science behind how a light bulb works is based on the principles of electricity and thermodynamics. Inside a light bulb, there is a thin filament made of tungsten that heats up when an electric current passes through it. This heat causes the filament to emit light, creating the glow of a light bulb. The bulb is also filled with an inert gas, such as argon, to prevent the filament from burning up.

2. How does the wattage of a light bulb affect its brightness?

The wattage of a light bulb refers to the amount of power it consumes. Generally, the higher the wattage, the brighter the light bulb will be. This is because the higher wattage allows for more electricity to flow through the filament, causing it to heat up and produce more light.

3. Can a light bulb produce different colors of light?

Yes, a light bulb can produce different colors of light. This is achieved by using different materials for the filament, such as halogen or fluorescent coatings. These coatings emit different wavelengths of light, which can appear as different colors to the human eye.

4. What is the lifespan of a light bulb?

The lifespan of a light bulb depends on the type of bulb and how often it is used. Incandescent bulbs have the shortest lifespan, lasting around 1,000 hours. LED bulbs have the longest lifespan, lasting up to 50,000 hours. On average, a light bulb will last for around 2,000 hours.

5. Are there any environmental concerns surrounding light bulbs?

Some light bulbs, such as incandescent and fluorescent bulbs, contain small amounts of mercury, which can be harmful to the environment if not disposed of properly. LED bulbs do not contain mercury and are considered more environmentally friendly. It is important to recycle all types of light bulbs to prevent any harm to the environment.

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