What is Glow: Definition and 47 Discussions

Maybe more of an optics/biology question than electrical, but... My wife wanted some lighting on a cabinet nick-knack shelf. I thought it would be fun/interesting to use a strip of RGB LEDs and a controller to adjust the light color to whatever we wanted, plus the LEDs would be less heat and...

A question about Glow in the dark Fluorescent chemicals can activated by UV, absorb energy at short wavelength then emit photons the human eye can see in the visible spectrum. Stop the UV source, the visible light emission stop. You cannot see anything. Electron returns to non-excited state...

As speed increases, the energy transferred from air friction must start to heat the aircraft. Eventually the plane will glow with radiating heat, such as a re-entering space craft. Presumably a plane can do something about this with cooling systems? Presumably there must be a heating limit to...

I'm trying to figure out why emission nebulae glow. I read various sites such as a NASA website explaining why they shine; 'The massive stars embedded within the nebula give off enormous amounts of ultraviolet radiation, ionizing the gas and causing it to shine.' The Britanica article on...

You have seen shirts with figures or drawings that glow in the dark at night. Is it composed of radium ink? Are there radium ink being used now or are all glow in the dark ink safe?

"Glow in the dark paint was applied to the lock, so a soldier could unlock the miniature bomb in the dark". I'm thinking that its unlikely 'glow in the dark paint' would be tritium based. More likely radium, which was used up to WWII for instrument dials etc. But I don't know. Backpack nukes...

I understand it as heat is simply the motions of atoms/molecules (kinetic energy). The warmer an object gets (a solid), the more the molecules are vibrating. Or possibly the other way around; the more vibrations, the more heat we say that the object has (right?). But what is happening when an...

Lets assume: emissivity of a human=0.91 T=310K Surface area body: 1.60 m^2 If we use the Stefan-Boltzmann Law we can find a value for the rate of emission of light by a human. Rate emission=762 J/s Given this rate of emission, why don't humans glow in the dark?

I am trying to understand the "strong" negative E field in the Aston Dark Space in the thin region close to the cathode or else even the cathode surface. See the diagram at: http://www.glow-discharge.com/?Physical_background:Glow_Discharges My question regards the "Electrical Field E" graph...

I'm talking hotter than T = 6000k. The higher the temperature, the more the curve in the attached figure would shift to the left (while at the same time getting higher). So the intensity peak would eventually fall back into the invisible portion (very small wavelength this time) of the...

Homework Statement For a high school physics class, I chose to build a tesla coil for a real world application assignment. I was able to build it fairly easily and it turned out great. Before presenting to the class next week, I've been seeing its effect on different types of light bulbs and...

Homework Statement Homework Equations Power of a bulb = I2R = V2/R The Attempt at a Solution [/B] From the ratings given on the bulbs using P=V2/R , we can conclude that resistances of the bulbs in decreasing order are R , P , Q i.e R has highest resistance and Q has lowest . Now...

Homework Statement A long, thin steel wire is cut in half, and each half is connected to a different terminal of a light bulb. An electromagnetic plane wave with E and B moves past the wire as shown. Part B: Suppose the wire were oriented parallel to the y-axis, as shown above. WOuld the bulb...

well, this may be obvious for many of you guys here! and I know it must be! but I don't seem to find any satisfying answer online. well, I know that when you heat up any kind of matter it will emit light depending on its temperature, for example, humans will emit infrared light the same as...

Hey guys, So recently I came across a weird phenomenon... Basically, I shined a red laser on a glow in dark surface and the laser could erase it. The fun fact is that before the laser erases the are, it makes it glow for a short time. You need good goggles to see the glow despite the intense...

I am trying to figure out how to make a "top to bottom glow" candle from paraffin wax. Can anyone advise me? Thanks.

hi, I just looking for Video on diffraction pattern of Electron, and noticed it produces green color pattern. Earlier in chapter, when cathode ray was discovered, it was mentioned that Green glow was Noticed. What is the reason for this green color?

Hello everyone, Can alpha emitters cause nearby (gasses or air) to be excited and glow like Radium or Tritium? Is there certain chemicals (maybe like phosphor) that are suitable for it?

Homework Statement Which statement is true? The color an object glows has nothing to do with how hot it is. As you heat an object, it glows more in the visible and less in the infrared. The day side of the Earth reflects more light, but the night side glows brighter in the infrared. You glow...

Homework Statement If a black blob and a white blob of the same size are each heated to 3000 Kelvin, the black blob will glow brighter.Question 11 options: True False Homework Equations none The Attempt at a Solution white because it reflects all incident rays?

Would the methods used to create glow in the dark e.coli readily work on other bacteria?

I have noticed that some of my tube amp power tubes are glowing slightly blueish. Why? It has been explained to me that this only means that the tube is ok. However, I find it fascinating! Because what is this blueish glow, really? To me it sounds like secondary emission of either the anode...

I have searched google and got no satisfying answer.Someone said that the overall resistance is less so as the voltage is same,the current increases.I don't think this is correct because the current for a single bulb is reduced.Can you give a satisfying answer?:confused:

I machined my own 7-segment display out of clear polycarbonate, each segment is about 1.5" long (it's a rather large display) and now it's time to add the LEDs. Turns out that the usual LEDs with the epoxy lens focus the light too tightly on one spot, so I get more of a dot rather than...

Hello, I was recently pulsing a coil at fairly high voltages (200-600VDC) using DC squarewave, at fairly high frequencies (100Hz - 1.3KHz). The output of the coil had a Neon bulb attached. I wasn't measuring current output at the time. At one point, i don't remember the frequency or...

So from my understanding of glow sticks, the decomposition of hydrogen peroxide provides electrons that excites the fluorescent dye and gives off that classical glow-stick light source. My question is, could one put a DC current over the solution and still theoretically obtain the same...

This is from a physics textbook All objects radiate energy continuously in the form of electromagnetic waves due to thermal vibrations of their molecules. These vibrations create the orange glow of an electric stove burner, an electric space heater, and the coils of a toaster Is the orange...

Hello, I'm an undergraduate student, doing an independent research project under a professor this summer. So the experiment I am working on involves using a glow discharge tube, with electrodes at two ends, to create and contain a plasma column. The purpose is to measure and analyze "wave...

Glow in the dark lake in Australia I came across this just yet and it looks amazing :O So I wanted to share with you guys :P

Homework Statement greetings why a bulb glow dimmer in beginning and then brighter when it is connected to a inductor?

why does the moon appear to glow from our view on earth? what causes the illumination?

Hi Title says what I am trying to do. I have an R/C Aircraft that was designed for a .40 glow engine and I want to convert it to electric and power it from a battery, and then solar. I am having issues of where to go next with my project, I have done some calculations, but stuck more on...

I'm looking for certain chemicals that glow with specifics colors when exposed to an electric current.

This may be a dumb question , let's say there are a bunch of people on the dark side of the Earth , these humans are emitting infrared photons and i am traveling by on a rocket ship if I travel fast enough will I see these humans glowing or emitting visible light .

I have a basic understanding of how the "glow in the dark" idea works. From what I can tell, electrons gain energy from light, "charge" up and move to a higher energy level, and when they no longer receive energy from the light (are in the dark), the electrons fall back toward a lower level and...

http://dsc.discovery.com/news/2008/01/08/hope-diamond.html

Well, the Koreans have done it again. Cloning a bunch of kittens from mom's skin cells certainly has some scientific value, but http://news.yahoo.com/s/afp/20071212/ts_afp/healthscienceskoreacloning" kittens? Why? To make it easy to find them in the dark? Not too useful since everyone...

So, I know that freezing them makes them last longer, but I was just curious... why? I've also heard that freezing them makes them glow less bright, and heating makes them brighter. Since its a chemical reaction, that doesn't use or produce heat I don't see how it should matter. Then again, I...

"glow" of emission lines vs. hot objects I was wondering how the mechanisms differ between the following two scenarios: A. The glow of emission lines (I think it has to do with the Bohr atom) B. The glow of hot objects (I think it has to do with Blackbody radiation)

"glow" of emission lines vs. hot objects I was wondering how the mechanisms differ between the following two scenarios: A. The glow of emission lines (I think it has to do with the Bohr atom) B. The glow of hot objects (I think it has to do with Blackbody radiation)

Is there any reason why most hot things alost always begin to get the tinge of red??

If all of the energy from the decay of 14C in your body could be captured and converted into electricity, how many "radioactive" people would be required to power a 100 W light bulb?

how to distinguish between the red glow of burning and the red glow of reaction?

If a bone gets hot enough, will it glow? Sorry if this is a weird question, this seems like the right forum to ask here. :confused:

What makes light "glow"? Hi, First post from a newbie... so forgive the naivety... Light is described as an electromagnetic wave/particle... but what actually gives light its "brightness", allowing it to illuminate the surroundings through which it travels? Also, another question if i...

I don't know where this will end up, but I am going to start it here. A few nights ago my wife and I where watching TV in the bedroom, we turned off the TV and the light over the bed and went to sleep. After a few minutes (maybe five or ten, I woke up and looked at the TV. It was glowing, but...

dear reader, is it possible to make an atom glow without another atom near it[?]