How does the resistance of a wire compare to the resistance of a bulb?
How does the resistance of a wire compare to the resistance of a bulb?
The resistance of a light bulb changes with the temperature of the filament in the bulb, and therefore changes with the voltage applied to the bulb. The resistance when it is operating at its maximum voltage may be 10 times as much as when the bulb is “off”.
(i) The length of the wire, resistance is directly proportional to the length of the wire. (ii) The cross-section of the wire, resistance is inversely proportional to the cross-section of the wire. (iii) The temperature of the wire, the resistance of wire is directly proportional to the temperature of the wire.
Does the bulb glow with copper?
Incandescent light bulbs have a small filament which when heated begins to glow and emit light. The reason the filament heats up is because it has a high resistance, which means that as electrons move through the filament, they lose a lot of energy.
Copper is a metallic mineral substance, and is used in the production of electric light bulbs because it conducts electricity very well. Copper,along with nickel, is used to make the wires that lead into the main body of the bulb.
An electric current flows when electrons move through a conductor, such as a metal wire. The moving electrons can collide with the ions in the metal. This makes it more difficult for the current to flow, and causes resistance.
Is copper used in lightbulbs?
For example, even a normal wire has some resistance. That resistance is so low that we usually ignore it, because other things in the circuit usually have far larger resistances, so it’s usually a good approximation to ignore the wire. But when it’s just the wire, you can’t ignore its resistance.
The filament in an incandescent bulb does not have a constant resistance. If you take a bulb and increase the voltage across it, the current increases too. An increase in current means the bulb gets hot—hot enough to glow. As the temperature increases, however, the resistance also increases.
Complete step by step answer It is a fact that we use tungsten for a filament. Tungsten has a high melting point and high resistivity.
The resistance of a wire is directly proportional to its length and inversely proportional to its cross-sectional area. Resistance also depends on the material of the conductor. See resistivity. The resistance of a conductor, or circuit element, generally increases with increasing temperature.
Copper wire cannot be used to create an electrical bulb filament, because copper wire has very low resistance. Therefore, the light does not shine until the current is removed.
The moving electrons can collide with the ions in the metal. This makes it more difficult for the current to flow, and causes resistance. The resistance of a long wire is greater than the resistance of a short wire because electrons collide with more ions as they pass through.
To answer your first question: A 100W light bulb has lower resistance because as long as the light bulb resistance is higher than the wire resistance, you can take advantage of the equation P=I squared R.
Why would copper be less suitable than tungsten as a filament in an incandescent light bulb?
Electrical resistance arises because charge carriers – electrons and holes – collide with imperfections in the material they are travelling through.
Resistance causes some of the electrical energy to turn into heat so some electrical energy is lost along the way. However, it is resistance that allows us to use electricity for heat and light. The heat that is generated from electric heaters or the light that we get from light bulbs is due to resistance.
They are much more efficient (much less resistance) than lightbulbs. All conductors have some resistance. For example, a piece of wire has less resistance than a light bulb, but both have resistance. The heat energy is enough to cause the filament to glow white-hot which produces light.
They are much more efficient (much less resistance) than lightbulbs. All conductors have some resistance. For example, a piece of wire has less resistance than a light bulb, but both have resistance. The heat energy is enough to cause the filament to glow white-hot which produces light.
