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Hot, really hot. Typically in the range of about 2000C to 2500C (3600F - 4500F). It would be pretty difficult to directly measure the temperature of the filament so you have to use something other than a thermometer for the measurement. It should be possible to estimate the temperature of the filament from the light spectrum. Basically, treat the light bulb like a perfect black body radiator and use Plank's Law (http://en.wikipedia.org/wiki/Planck%27s_law) and the light spectrum of the bulb (for example http://www.graphics.cornell.edu/online/measurements/source-spectra/index.html) to calculate the temperature. Another way, which is a bit easier, is to use basic electronic theory to calculate the temperature of the filament that is required to produce the manufacturer's specifications for the bulb. For example, consider a typical 100 watt, 120 VAC light bulb with a tungsten filament. The bulb consumes (and radiates) 100 watts of power. A light bulb is a purely resistive load so Power=(Voltage)*(Current). Plugging in 100 watts as the power, 120 as the voltage (actually, that's the RMS voltage), and solving for current we get an RMS current of 0.83 amps. Since the bulb is just a resistor it obeys Ohm's Law; Voltage=(Current)*(Resistance). Our voltage is 120 and we determined the current to be 0.83 amps, so the resistance of the bulb when it is operating is 120/0.83= 144 ohms. If you take a 100W incandescent light bulb and measure its resistance at room temperature you get a value of about 15 Ohms. The difference between the room temperature resistance and the resistance when the bulb is operating is due to the affect of temperature on the filament's resistance. Metals (and conductors in general) increase their resistance as they are heated. The resistance at a particular temperature can be calculated with; R=Rref*(1 + alpha(T-Tref)] Where, R is the resistance at temperature T degrees Celsius. Rref is the resistance at a standard temperature Tref (often 0C or 20C). Alpha is the "temperature coefficient of resistance" for the material. For tungsten alpha=0.0044/C with a Tref of 20C (68F). If we assume that the 15 Ohm resistance at room temperature is close enough to the value at 20C (68F) then we can use Rref=15 ohms and R is the 144 ohms we calculated from the wattage and voltage of the bulb. Plugging these numbers into the equation; 144=15*(1 + 0.0044*(T - 20)) Solving for T (the temperature required to get the filament's resistance to 144 ohms) we get T=1975C (about 3600F). That's pretty hot! The filaments temperature will change if the applied voltage changes. The temperature will also be different from light bulb to light bulb (even if they have the same voltage and wattage ratings) since no two bulbs are exactly alike. An individual bulb will also change as it ages and as a function of the temperature outside the bulb.
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ANSWER: Flourescent bulbs. They have no filament and they light up. They have argon gas and a small amount of mercury in them. When electricity is added, the argo…n and mercury atoms get excited and collide against each other and create light. The light is ultraviolet light and if the bulb is not coated inside with phosphorous, you have a black light.
It is the extremely thin wire inside the bulb. It is so thin that when the electricity goes through produce light, when that filament breaks the bulb is not good.
Most simple incandescent light bulbs are made of a thin section of tungsten through which the current flows. This section of tungsten is called a "filament". The tungsten …filament has electrical resistance and so is a resistor. As a resistor it develops a voltage drop. This voltage drop multiplied by the amperage passing through it equals the wattage of the bulb. The heated tungsten gets to thousands of degrees above room temperature and becomes hot enough to produce yellow-white visible light. As a resistor, the tungsten light bulb has a positive resistance coefficient. This means that the electrical resistance goes up when the filament becomes hot. For example, a 100 watt light bulb operated at 120 volts - it does not matter if it is AC or DC for this calculation - will have a resistance of 144 ohms when hot and draw .833 ampere. When cold the filament typically has a resistance of only 10 ohms which increases as the filament heats up.
An incandescent bulb.
Bulb filament can reach temperature from 3410 degrees Celsius to 6300 degrees Celsius. No it can't. I think you're totally mistaken about how hot a filament can get. First of …all, the temperature of a filament can't go above it's melting point. Secondly, I read that Tantulum Hafnium Carbide has the highest melting point of any known substance at 4215 degrees C. Besides, bulbs have a tungsten filament which has a melting point of 3422 C. It's slightly possible that for some bulbs, they mix tungsten with something else to raise the melting point but since nothing has a higher melting point than Tantulum Hafnium Carbide, the filament can't possibly get hotter than 4215 C by being 6300 C.
Modern light bulb filaments are usually Tungsten not Carbon. However early bulbs used things like silk coated with Carbon. Filament means thin thread. The bulbs are filled… with inert gas like Argon to stop the filament from burning up with oxygen. Arc lamps use Carbon rods though.
Usually Tungsten. Carbon filaments were used first, but scientists found that tungsten works for a far longer time period. Unfortunately, most filaments designed today don't l…ast near as long as the bulb is rated at. Just put a dated replacement sticker on a light bulb and see when the next time you replaced it how long it went. You will be surprised.
Usually a Tungsten alloy.
The filament of an incandescent light bulb is actually significantly hotter than lava. Temperatures may exceed 4,000 degrees in some bulbs.
Filaments in incandescent bulbs are usually around 3000º C or 5000º F.
An electric current flows through the filament which is usually made of tungsten because its melting point is the highest of all metals. The filament heats to around 3000 …degrees C and becomes incandescent, radiating heat and light by what is technically called black body radiation.
The filament in a light bulb forms resistance so that heat can happen. The electricity then converts to light energy and heat energy so that the light will shine.
It passes an electric current and its temperature rises to about 3000 degrees C so that it is white-hot and gives off light. Unfortunately this type of bulb also produces …a lot of heat, which is just wasted power.
That is the result of resistance in the wire. In energy terms, some of the energy in the electric current is converted into heat.