The resistance of the filament in a light bulb is
(voltage at which the bulb is designed to operate)2/(the rated power/watts of the bulb)
Tungsten (pronounced /tʌŋstən/), also known as wolfram (/wlfrəm/), is a chemical element with the chemical symbol W and atomic number 74. Tungsten is one of the heaviest materials after gold, for the density of tungsten is 19.25  g•cm3(near r.t.).Tungsten is one of the Nonferrous Metals, and also it is as molybdenum and rare earths which are Refractory Metals.It is also used in eletrical bulbs as filament.
A lamp with a thick filament will draw more current. What restricts the current flow in the filament is the resistance of the filament which increases as the temperature of the filament increases. A thin filament requires less energy to get heated up that a thick one so less current to achieve threshold resistance. Also a thick filament provides a broader path for current so there is less resistance per increase in degree centigrade. For these two (closely related but distinct) reasons it will require more current for the filament to get heated up to threshold resistance.
A flash light generally makes light using a light bulb, which contains a filament. The filament is typically made from tungsten. It is very thin, but capable of withstanding extremely high temperatures. Electricity, from an internal power source, is passed through the filament. The filament has a resistance, so the current creates a very large heat in the wire. Because the wire is so thin, it heats up very quickly, and this excess energy is given out as light, and heat.
Tungsten's many alloys have numerous applications, most notably in incandescent light bulb filaments, X-ray tubes (as both the filament and target), and superalloys. Tungsten's hardness and high density give it military applications in penetrating projectiles. Tungsten compounds are most often used industrially as catalysts.
Filament
Electricity creates heat when flowing through a resistor such as the filament in a tungsten light bulb, and, since the heat can not be readily conducted away in the near vacuum inside a light bulb, the heat eventually raises the temperature of the filament to a value that leads to radiation of light from the hot filament.
The incandescent light bulb. The tungsten filament lights due to it's resistance of the current flowing through it.
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.
To find the length of the tungsten filament, you can use the formula: R = ρ * (L/A) Where R is the resistance (120 ohms), ρ is the resistivity of tungsten, A is the cross-sectional area (5x10^-9 m^2), and L is the length of the filament. Rearranging the formula to solve for L gives: L = R * A / ρ Given the resistivity of tungsten at 20 degrees Celsius, you can calculate the length of the filament.
The filament is a special metal composition of tungsten that conducts current and heats up and emits light as a result of the current and its internal resistance.
the simple answer is resistance, the filament is a very fine wire (usually tungsten) that heats up and glows when power is applied
the simple answer is resistance, the filament is a very fine wire (usually tungsten) that heats up and glows when power is applied
The slope of the voltage-current (VI) characteristics for a tungsten lamp is positive because as the current increases, the temperature of the tungsten filament rises, leading to an increase in resistance. This phenomenon is due to the positive temperature coefficient of resistance of tungsten, where the resistance increases with temperature. Consequently, the relationship between voltage and current becomes non-linear, resulting in a positive slope in the VI characteristics. This behavior is typical for incandescent lamps, where the filament's temperature significantly affects its electrical properties.
Inside a tungsten-halogen bulb, electrons flow through a tungsten filament. The filament heats up and emits light.
i believe it is cadnium.
What is Tungsten
tungsten