[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

View post   
File: 10 KB, 500x500, 1295846595885.png [View same] [iqdb] [saucenao] [google]
4060176 No.4060176 [Reply] [Original]

haaaaaiiii guys ^^

ok, so I want to know:
WHAT MAKES LIGHT SO DARN FAST??

I mean, I can imagine it being fast from a super nova explosion, but a lightbulb isn't even moving.
It just gets hot, then suddenly WHIZ tons of photons come blasting out at LIGHT SPEED.
that's FAST.
Why is it so fast? I know light has almost no mass, so it's not momentum, right? Why doesn't light stop when it hits something? Why is it turned to heat?
And if it's a mirror, why does it continue to go just as fast after it hits?
And of course, does light have acceleration?
Like when the lightbulb filament sends out that first speck of light, is it going light speed, or below that?

Thaaaaaank you >^,^<
this is the third time posting this, please be in the right place -,-;;

>> No.4060179

>>4060176
From light's point of view, it's never travelling. Wrap your head around that.

>> No.4060181

>>4060179
aaaaaaaaah. ouch
ok, so wait
what does that
mean...? ...
I'm really confused @,@;
How does that even work??

>> No.4060193 [DELETED] 

>>4060181
pleeeaase help me!

>> No.4060203
File: 13 KB, 400x400, cow_on_ground_lol.png [View same] [iqdb] [saucenao] [google]
4060203

>>4060193
http://en.wikipedia.org/wiki/Light

>> No.4060206

Light doesn't travel, it went in to space once and saw a cat, now it is afraid to leave the lightbulb.
Some other protons that broke away go to see it sometimes, and that is how we can see in a dark room - flicking a light switch actually sends little invitations to photons to visit for tea.

>> No.4060208

>>4060203
boo, I tried that but it's too complex for me >,<
too many big words.

>> No.4060210

I can't figure out whether you're trolling or you're always annoying like that.
Light is fast because it's fast. It has no mass so it can have velocity higher than stuff with mass. You can never provide a clear answer to a "why" question. Ultimately, you will always reach a point where you have to deal with the fact that some things are just that way.

>> No.4060215

In a lightbulb, electrons in the tungsten filament are exited by the electricity into higher energy levels (pushed into higher orbits around their nuclei, which are trying to pull them into each other due to differences in electric charges, so this takes alot of energy.) When these exited electrons fall back into lower orbits they give off the energy they used to climb into a higher orbit. This energy is released in the form of a photon, which, as you pointed out, has very little mass, so the energy its givin is enough to push it out at the speed of light. The level of energy it's given determines its wavelength (color), and correspondingly its total energy, but it will always travel the speed of light.

If that doesn't clear it up feel free to ask, and I'm no expert so I'm not guaranteeing its 100% correct.

>> No.4060219
File: 294 KB, 500x367, cutey_Emma_lav.png [View same] [iqdb] [saucenao] [google]
4060219

I tried to gave a basic answer in the original thread
>>>/g/21229051

>> No.4060234

>>4060215
Yeah, that makes a little sense..
so could you go sailing with light?
If you have a huuuuuuuuge sail, made of a perfect mirror in SPACE
would the light from the sun be able to push it and make it move, even a little?

...also, how come glass is clear..? o,o;
that's really freaky, that a thin sheet of metal won't let much light through, but a thick window can.
I know that gamma rays have a higher frequency? than visible light, but surely a solid made of what was once sand wouldn't let visible light through, right?

And why is light hot? Is all light hot? Is gamma as hot to some materials as infrared is?
Or what?
lol, sorry for all the questions ^^;;
I'm just curious

>> No.4060238

>>4060176

Google it, you weeaboo faggot.

>> No.4060245
File: 30 KB, 215x608, 1287319229985.png [View same] [iqdb] [saucenao] [google]
4060245

>when the lightbulb filament sends out that first speck of light, is it going light speed, or below that?

>> No.4060248

>>4060234
http://en.wikipedia.org/wiki/Solar_sail

yes light can push objects, it's pushing all of us right now.

seriously though stop the fucking childish typing thing now

>> No.4060253
File: 44 KB, 410x303, sage.jpg [View same] [iqdb] [saucenao] [google]
4060253

sage

>> No.4060268

>>4060234
Solar sails exist, they're really thin and light sheets of metal coated polymers that work because light hitting it pushes it forward.

Glass is clear because light moves by absorption re emission. Metal and wood and opaque stuff reflects light back away from it. In glass and in water or other liquids for that matter, photons are absorbed by atoms as energy, then re emitted in a slightly different direction. Light coming through a window it bounced back and forth by the atoms but comes back out the other side more or less in the same direction. it does change direction slightly, thats why theres is refraction, like when a straw in a glass of water looks broken.

And as far as I know, light isn't really hot, but it just carries energy, which is just transferred to objects in the form of heat when it hits them.

Also, light never ages. Because time slows down as you speed up, and light is moving at the speed of light, no time passes for them, at least from their perspectives.

>> No.4060282

>>4060234
and there is no such thing as a perfect mirror.

Perfection is impossible, unless its a woman youre in love with :P

>> No.4060283

>>4060248
agreed please stop

but anyways an emitted photon does not car if it is made by a light bulb or a star. It has to do with what is happening on a scale of the nucleus. most visible light is produced from an electron jumping to a different energy state, and in doing so it looses energy, and thus emits a photon equal to the energy that was lost. that's basically visible light

>> No.4060292

>>4060268
>>4060248
...light doesn't age?
Weird.
So then my lightbulb, when it's on and glowing, does the filament stop aging too because it's now glowing?
It's not moving in my eyes, but if it's glowing and giving off light, then that means it's atoms are vibrating reeaaally fast, fast enough to make light.

Bluh, I'm really confused now! Obviously, the filament ages, but why? What does it even mean to age?
Just atomic decay? Oxidation and in humans?

>> No.4060303

>>4060292
the atoms in the filament age at the same rate as everything else stationary relative to them. Objects moving faster than other things age slower than the slower ones do. The photons don't age from their perspective because they are moving at the speed of light, where time stops. Light will take millions of years to reach earth from other stars, but the photons themselves aren't millions of years old FROM THEIR PERSPECTIVE. from ours yes, they are millions of years old. Read the elegant universe by Brian greene.

>> No.4060304

>>4060292
And, just a question, how old are you?

>> No.4060305

>>4060292
light doesn't age in the sense that time stops for the photons

>> No.4060313

A faggot more annoying than teacunt/harriet/ek has finally graced this board.

>> No.4060318
File: 25 KB, 338x277, 1295031363726.jpg [View same] [iqdb] [saucenao] [google]
4060318

>What does it even mean to age?
try asking those few animals with negligible senescence

>> No.4060317

>>4060313
he/she only types annoying
she seems smart enough to be able to ask questions, at least

>> No.4060329

>>4060303
The elegant universe?

I never even thought about reading a book about this
Do people even write science books? Isn't it all articles and boring stuff?

well, what else should I get? I'll go to the library! ^^

>> No.4060330

>>4060292
Light bulbs die not because they've run out of light, but because the filament is kept at such a high temperature while on, small amounts of it vaporise and so when the filament gets too thin to take the current it completely melts and therefore no more continuous circuit and no more light.

>> No.4060335

>>4060329
Holy shit are you fucking 6 years old? No shit there are books on this.
>trolldetected.jpg

>> No.4060344

>>4060303
Time stops? That can't possibly be right... I mean... what? How can it travel at speed if time stops? Why doesn't light just teleport? what the fuck.

>> No.4060346

>>4060318
Senescence is caused by DNA damage (of which there are several kinds). I don't think anybody in a related scientific field would disagree with this definition, but you are obviously more than welcome to prove me wrong.

>> No.4060355

>>4060303
waaaait~

this means... Why does light not feel time?
I mean, is it only because of speed? So if someone else went that fast, they also wouldn't age?
Why not?

>>4060335
and sorry, I knew there were science books for kids and stuff, but I hadn't really thought of getting a book. I'm online too much, I guess ^,^;;

>> No.4060356

>>4060344
Because the photon is moving at the speed of light, time from IT"S PERSPECTIVE stops. If it were to stop short somewhere other than its starting position it would, from its perspective, look like it teleported instantly. From anywhere else, you can watch it move from point a to point b at the speed of light in regular time.

Look up relativity.

>> No.4060360

>>4060330
Yes, I know that.
But the matter that is actively glowing, does that age while it's still glowing? I'm sure it burns/vaporizes, but does it age in time? ..
what is time anyways?

>> No.4060368

>>4060344
What are you talking about? From the perspective of a single photon, it doesn't really "travel" at all. If a photon had the gift of perception, it would at one moment exist, and at the exact next moment it would hit something (and either "die" [read: be absorbed] or get deflected). It doesn't matter whether or not the photon travelled for 10 minutes or 10^90 years from our perspective.

>> No.4060371

>>4060355
The elegant universe isn't for kids, but its not impossible to understand for a layman. And yes, if you could move the speed of light no time would pass from your perspective. However, its impossible for anything with mass to reach the speed of light. If you could go 99.99999% the speed of light, time would procede normally from your perspective while the outside world moved by incredibly fast. The other way around, if you were moving that fast, to everyone else your actions (not your speed) would seem to be incredibly slow.

>> No.4060378

youre a bunch of aspie faggots for replying to this attention whore

shes probably a fat ugly disproportionate cow IRL

>> No.4060381

OP is probably Sokonoko again

>> No.4060384

>>4060371
To put it another way, If i took off right now towards a nearby star at 90% the speed of light, and it took me 30 years to make a round trip journey from earths (and your) perspective, it would take less time from my perspective (maybe something like 20 yrs im not gonna do the math) because I was moving close to the speed of light compared to you. Time seems to go by at a normal pace for both of us all the time from our own perspectives all the way for both of us however.

>> No.4060386

>>4060378
the point of /sci/ is to ask and answer scientific questions. I don't give a fuck what she/he looks like irl.

>> No.4060388

>>4060371
Why?
I don't see why that would make sense at all.
I don't have a car yet, but even when I'm riding in one and going fast, nothing seems slower, nor would I expect anything to go slower even if I go much much faster. Even at lightspeed, why would it seem slow to me? My brain would still go the same speed and have the same... um frequency? clock rate? as usual, right?
Or no?
I'm really confuzzled right now @,@

>> No.4060395

>>4060371
Intuitively, I'd say that someone accelerated to c (which is obviously impossible as it stands) would literally not be able to do anything, and would be locked into the position they entered c in forever (from our perspective), and an instance from their own perspective, no matter how long their journey.

>> No.4060397

>>4060378
I'm just asking questions..
I'm sorry if I type differently than you. I'm just use to it, I guess.
sorry.

>> No.4060398

>>4060388
No vehicle ever made by humans has gone a large enough fraction of the speed of light to make time dilation noticeable to a human. cars dont come close to going fast enough for this to be noticeable. And no, from your perspective time always moves at the same rate. its other people that will seem to move at a different speed no matter what.

>> No.4060405

and you still haven't answered me as to how old you are. I'm not expecting most 13 year olds to get this. it took me alot of reading and thought to understand this as much as I do now, which i admit is not a whole lot.

>> No.4060416

>>4060386

if his or her typing doesnt piss you off, then youre a faggot piece of shit aspie nigger

>> No.4060423

>>4060416
If it pisses you off you are the asspie. Faggot.

>> No.4060428
File: 18 KB, 379x374, 1319518449448.jpg [View same] [iqdb] [saucenao] [google]
4060428

>>4060176
>haaaaaiiii guys ^^
>Thaaaaaank you >^,^<
>-,-;;

>> No.4060432

>>4060423
she isn't gonna fuck you brah
it's probably a dude anyway

>> No.4060433
File: 79 KB, 1464x804, 1295795468760.png [View same] [iqdb] [saucenao] [google]
4060433

>>4060423
>>4060416

>> No.4060437
File: 24 KB, 500x332, 1320348093003.jpg [View same] [iqdb] [saucenao] [google]
4060437

>>4060432
no fucking shit. Who said im in this to get laid? I'm not gonna go fly across the fucking country to land in Chris Hansen's lap. Retard.

Is it so hard to accept that I'm trying to help someone understand the universe? I find the subject fascinating.

>> No.4060440

>>4060398
>>4060384

Why does light not feel time though? What is it about going fast that makes time move slower?
I don't understand that. You mean like red/blue shift stuff?
Is it purely perception for a human, or would atomic decay continue at the same rate, like if a bar of some radioactive metal was moving lightspeed, would it continue to decay at the same measurable rate that it would on earth, or would it stop? And why?

>>4060405
Yeah, I'm a 14 year old girl and just BARELY get this, but today a friend asked me a question that blew my mind, so I went to the only website I knew of with a science themed board on it. Sorry for bugging you >,>

>> No.4060445

>>4060423
>>4060428
>>4060432
>>4060433
Despite the fact that OP types like a 9 year old attention-whoring aspie retard, you guys are not contributing to this thread in any constructive manner. All you are doing is making sure that people who actually know what the hell they are talking about, don't post. In replying to you I've further deteriorated the quality of this thread, but I hope it will be worth it when you consider doing the same in future threads.

>> No.4060449

>>4060440
One theory I read was that everything is moving at the speed of light all the time through 4 dimensions. The first three the the spatial one, foward and back, left right, up down. The 4th is time. When something is standing still, all its movement is through time. When something moves spatially, like a rocket going up relative to the earth, it takes some of the energy its using to go foward in time to move through space. Therefore, it has less energy to move through time and as a result moves slower through time.

>> No.4060450
File: 98 KB, 700x700, 1316110388133.jpg [View same] [iqdb] [saucenao] [google]
4060450

>>4060445
you have no idea how terrible i feel about that

>> No.4060451

>>4060445

are you a robot?

cause you write like one

you must be really fucking boring

>> No.4060452
File: 38 KB, 600x273, 1291509309326.jpg [View same] [iqdb] [saucenao] [google]
4060452

>knows good deal of sciency terms
>asks if LIGHT travels below the speed of LIGHT
>>^,^<
3/10
made me chuckle

>> No.4060459

>>4060437

>hurp durp i´m trying to help retards learn the little knowledge i have of the universe, and i find it "fascinating" hurp durp i´m a worthless piece of shit hurp durp

>> No.4060469

>>4060459
Ow, this really hurts coming from the worthless piece of shit posting a non-helpful response. Get the fuck out faggot.

>> No.4060470

hi every1 im new!!!!!!! *holds up spork* my name is katy but u can call me t3h PeNgU1N oF d00m!!!!!!!! lol...as u can see im very random!!!! thats why i came here, 2 meetrandom ppl like me ^_^... im 13 years old (im mature 4 my age tho!!) i like 2 watch invader zim w/ my girlfreind (im bi if u dont like it deal w/it) its our favorite tv show!!! bcuz its SOOOO random!!!! shes random 2 of course but i want 2 meet more random ppl =) like they say the more the merrier!!!! lol...neways i hope 2 make alot of freinds here so give me lots of commentses!!!!DOOOOOMMMM!!!!!!!!!!!!!!!! <--- me bein random again ^_^ hehe...toodles!!!!!

love and waffles,
*~t3h PeNgU1N oF d00m~*

>> No.4060476
File: 182 KB, 720x951, 1293821383031.jpg [View same] [iqdb] [saucenao] [google]
4060476

>>4060459
not him but you act like 14 years old

>> No.4060486

>>4060470
Wow. That reminds me of my /b/ days..
I wonder if that was a real girl and I wonder what she's doing now..
I wonder if she's still weird, or if she's now in college, a husband or wife? Kids? A job?
Kinda sad... I used to be a kid too.

>> No.4060487

So, given a spacecraft that can achieve 100% lightspeed, AND somehow has the ability to slow itself below lightspeed (work with me here), if a person were to travel on this ship, any journey, no matter how far, would feel nearly instantaneous to him/her?

>> No.4060493

>>4060487
Yes, but nothing with mass can reach light speed. It would take infinite energy. And it would still take however long from an outside perspective. If i want to get to a star 100 ly away and i go at light speed, to me it would take no time at all, but to the outside world it still took me 1000 years to get there.

>> No.4060494

>>4060487
Yes!!
Answer this, this will really help me understand this stuff! ^,^

And WHY
like, I am just brain boggled right now. I can't even think about how going really fast makes everything around you go slow.
Like, not just feel slow, but it actually goes slower? Or you go faster?

Is slow and fast even words to use? Time is really confusing... bluh -,-;

>> No.4060501

>>4060493
I meant 1000 ly and 1000 years. This also assumes you don't need to accelerate to light speed, but you of course would. In all likelihood, real space travel will be done on generation ships where 20 or 30 generations of people life their entire lives on the ships before they reach their destination moving at a small fraction of lightspeed.

>> No.4060503

>>4060493
Right, to me 100,00 light years would be the blink of an eye, but to the rest of the universe my journey too 100,00 years.


I'd be interested in seeing the equation that proves time is not a contant, or whatever.

>> No.4060504

>>4060494
Yep, God is amazing isn't he?
don't forget to pray to our lord and savior jesus christ tomorrow.

>> No.4060505

>>4060494
As for the why, read this
>>4060449

Its just an intrinsic property of the universe, like why negative and positive charges attract.

>> No.4060508

>>4060504
-4/10 troll, trying to make me sound uberchristian. I am christian but I don't just spout religious gibberish when talking about shit. Go back to /b/ faggot.

>> No.4060514

>>4060508
And that doesn't mean i think the earth is 4000 years old either. I'm not retarded, but I have faith in a higher power than man.

inb4 religious discussion

>> No.4060513

>>4060449
Whoa, is this a well regarded theory? Makes sense to me at first glance, but I'd like to read more. Got links?

>> No.4060515

>>4060513
I'm not sure how accepted it is in the scientific community, but it was in some book I read on the subject, I'm pretty sure it was The Elegant Universe.

>> No.4060516

>>4060219

Are photons emitted or generated and everywhere in the universe there's is something that turns into photons?

>> No.4060526

was googling and saw this
http://www.nature.com/news/2011/110603/full/news.2011.346.html

explain.

>> No.4060539

>>4060526
"If verified, the finding would be one of the most unusual experimental proofs of quantum mechanics in recent years and "a significant milestone"

I'm not a physicist. I'm just a guy stuck in his dorm for thanksgiving break who knows a little about this kinda shit. I don't know, especially since its some brand new UNEXPLAINED phenomenon. Don't take this as fact, but I'd imagine it has something to do with what the article talks about, vacuum energy. Don't ask me what that is, idk, no one does We don't even know if it exists, but it would explain alot of shit like the universe expanding. If I could I'd freeze myself for thousands of years to see what the state of knowledge on this stuff is, but it's likely we'll never really figure everything out. The universe (or mulitverse) is a huge mystery.

>> No.4060543

>>4060539

>we dont know if vacuum exists

Are you serious?

>> No.4060552

>>4060526
its just a way to turn kinetic energy into light, it proves the virtual particles are real because apparently some physicists wont except it (even though alot already excepted it) so i dont get the hype about it. it just proves our physics is, indeed, correct, not anything new.

>> No.4060553

>>4060543
Learn to read retard. Vacuum ENERGY. Energy that theoretically might be stored in the quantum foam certain theories say make up the vacuum itself.

>> No.4060555

>>4060539
well, I've heard about virtual particles before...
but this is different. Actually MOVING those particles before they fade seems to make them stay.
Is this how the big bang happened? A random fluctuation suddenly introduced matter to what was before?

>> No.4060564

>>4060552
seems me like a weird manifestation of E=mc2.

and>>4060555
read; I am not a physicist. I don't know. There is a theory that says the universe is a mulidimensional brane that came into being when 2 similar branes smashed together and created our universe

>> No.4060567

>>4060553

Vacuum is energy, why are you denying this?

>> No.4060573

>>4060567
When you post
">we dont know if vacuum exists

Are you serious?"

It looks a hell of a lot like you just asked whether or now i knew vacuum exists or that I think space is filled with air or some stupid shit like that.

>> No.4060577

>>4060573

It's what you said. What do you actually think vacuum is other than energy?

>> No.4060585

>>4060564
....what in the world is a brane? ;;o,o/"
sounds scary.

>>4060552
How are they real? What does that mean for us?
Isn't a vacuum supposed to be utterly empty of everything? (and scares the kitty ^^)
How does something come from nothing?
I don't really believe in a god, but this sounds really freaky o,o

>> No.4060586

>>4060577
If I said something against that I didn't mean to,I'm dead tired.

Also, read; i am NOT a physicist, and as I said i can't verify everything I say.

>> No.4060597

What would happen if you sucked the energy out of a bunch of photons? Would they just sit there? How would that look, light not traveling?

>> No.4060602

>>4060586

They fade away. See black holes.

>> No.4060603

>>4060585
I'm not going to even begin to explain that one. I'm tired, and its alot of visualization and math I don't pretend to begin to understand. Just wikipedia it if youre interested. Watch history channel too. Inbetween HURR DURR NOSTRADAMUS 2012 and HURR DURR SWAMP PEOPLE they have alot of good shit on this kinda stuff. Same with the science channel.

And I repeat, I don't know everything on this, its only a minor hobby of mine to read up on it.

>> No.4060615

>>4060585
>>....what in the world is a brane? ;;o,o/"
It's stuff like this you should be looking up yourself. http://dictionary.reference.com/browse/brane

>>Isn't a vacuum supposed to be utterly empty of everything?
That's the classical definition of a vacuum.

>>How does something come from nothing?
The virtual particles spontaneously generated in a vacuum don't come from nothing. The leading theory is that even space itself has energy, and that the virtual particles take energy from space in order to manifest themselves.

>> No.4060623

>>4060597
It is impossible to "suck the energy out" of a single photon.