A light bulb is nothing more than a piece of wire inside an evacuated (gasless) glass envelope. Light is heat, and the wire is made of such materials to promote great heat to develop quickly. Removing all gasses from the glass envelope makes sure that the wire doesn't just burn - instead, it glows with bright light.
Now, it uses a LOT of energy, transforming it into heat and light. As such, it is an effective current limiter - in a conductor, heat equals resistance.
Calculate it and you will see - a 100W light bulb at 230V will have to use around 0.45A to generate that much power, and in order for it to allow exactly this much, it needs to be a resistor (a 500ohm resistor, to be precise).
230V / 500ohm = 0.46A, and 0.46A * 230V = 105.8W
And that is why a light bulb is an effective resistor.
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∙ 13y agoA light bulb adds resistance to a circuit because the filament in the bulb resists the flow of electrical current. This resistance causes the electrical energy to be converted into light and heat, which are the outputs of the light bulb.
You can make a bulb shine with a fainter light by reducing the voltage supplied to the circuit. This can be done by adding a resistor in series with the bulb to limit the current flowing through it, or by using a dimmer switch to adjust the voltage. Decreasing the power to the bulb will result in a dimmer light output.
When resistors are connected in series, their resistances add up. So, if you have three light bulbs with X ohms of resistance each and connect them in series, the total resistance in the circuit will be 3X ohms, which is greater than the resistance of a single light bulb.
Adding a third bulb in parallel will decrease the total resistance. In a parallel circuit, the total resistance decreases as more resistors are added because the equivalent resistance is calculated differently compared to a series circuit. This is because there are multiple paths for current to flow, reducing the overall resistance of the circuit.
When more light bulbs are added in parallel to a circuit, the total resistance of the circuit decreases. This is because in a parallel circuit, the reciprocal of the total resistance is equal to the sum of the reciprocals of the individual resistances. More paths for current to flow mean less overall resistance in the circuit.
You can make a light bulb in a circuit brighter by increasing the voltage supplied to the bulb. This will cause more current to flow through the bulb, resulting in increased brightness. Just be cautious not to exceed the voltage limit of the bulb to prevent damage.
to complete the circuit you have to add 1 light bulb.
You can make a bulb shine with a fainter light by reducing the voltage supplied to the circuit. This can be done by adding a resistor in series with the bulb to limit the current flowing through it, or by using a dimmer switch to adjust the voltage. Decreasing the power to the bulb will result in a dimmer light output.
As you add more bulbs to a series circuit that means that the bulbs are in series to one another, therefore the total resistance is the sum of the individual resistance of the bulbs. If you add bulbs of the same resistance,then the rate at which the resistance changes will increase in a constant manner provided the current source is not altered. For instance if the bulb you are using is rated 20v,60w, then the current passing via the bulbs in series is the square of the voltage divided by the power in this case the current is approximately 7amperes.
If a rheostat is connected in parallel with a light bulb, the setting of the rheostat should have no effect on the performance of the light bulb, as long as the power supply is able to maintain its output voltage and deliver the current demanded by their parallel combination.
The bulb becomes brighter unless it is too much till it shot-circuits.
When resistors are connected in series, their resistances add up. So, if you have three light bulbs with X ohms of resistance each and connect them in series, the total resistance in the circuit will be 3X ohms, which is greater than the resistance of a single light bulb.
Adding a third bulb in parallel will decrease the total resistance. In a parallel circuit, the total resistance decreases as more resistors are added because the equivalent resistance is calculated differently compared to a series circuit. This is because there are multiple paths for current to flow, reducing the overall resistance of the circuit.
If the two batteries are in series, add the voltages. Then use Ohm's Law to calculate the current (that is, divide the voltage by the resistance).
When you add a light bulb, you are adding a load, which performs a function - in this case, it converts electrical energy to light and heat energy. When you add an ammeter, most of the time you intend to measure the current in the circuit, which is the function of the ammeter. Thus the two electrical components differ in their function and does different things when added to a circuit.
When more light bulbs are added in parallel to a circuit, the total resistance of the circuit decreases. This is because in a parallel circuit, the reciprocal of the total resistance is equal to the sum of the reciprocals of the individual resistances. More paths for current to flow mean less overall resistance in the circuit.
Yes. Each light bulb is just another resistor in a series circuit, where you add the individual resistances to get the total resistance (unless the bulbs are set up in parallel, where adding a second identical light bulb would cut the total resistance in half).
The brightness of a standard bulb is directly proportional to the amount of voltage drop across the bulb itself. Thus, to increase the brightness :-Pass more current across the bulb by reducing the resistance of the circuitIncrease the voltage across the bulb, or the circuit. Change the supply.