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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 ago
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How would you make a bulb in a circuit shine with a fainter light?
If you add resistance to the circuit the bulb will shine with a fainter light ... the higher the resistance is the fainter it will shine
When more light bulbs are added in parallel to a circuit what happens to the total resistance of the circuit?
"http://www.tpub.com/neets/book1/chapter3/1-26.htm" This site explains how to calculate the resistance, but it decreases the resistance when you add more.
There are two light bulbs in a circuit wired in parallel a third bulb is added what is the effect on tolal resistance of adding the third bulb?
Adding any additional element in parallel will reduce the combined resistance. Do some sample calculations to get a "feel" for this: Total resistance (R) is calculated as 1/R = 1/R1 + 1/R2 + 1/R3... In other words, take the reciprocal of the individual resistances, add them, and then take the reciprocal of the result.
How could you make a light bulb in a circuit brighter?
-- Without changing the bulbs, increase the voltage of the battery or power supply. -- If the bulbs are in series, take one out of the circuit, and replace it with a piece of wire. -- Replace incandescent bulbs with others whose filaments have lower resistance. -- Replace incandescent bulbs with fluorescent tubes. -- Replace incandescent bulbs with LEDs.
What will happen to a bulb if you add more batteries to a simple circuit?
It gets brighter and brighter - until it burns out.
How would you make a bulb in a circuit shine with a fainter light?
If you add resistance to the circuit the bulb will shine with a fainter light ... the higher the resistance is the fainter it will shine
how to use circuit in sentence?
to complete the circuit you have to add 1 light bulb.
What happens when you add a resistor to a series circuit with a light bulb?
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.
What will happen to the resistance and the brightness if you add a light bulb to the circuit?
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.
If you add an extra battery to a circuit containing a bulb how will this affect the bulb?
The bulb becomes brighter unless it is too much till it shot-circuits.
What is the current in the circuit contains two 1.5 volt batteries and 6 ohm light bulb?
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).
How is adding a ammeter to a circuit different from adding a light bulb?
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 what happens to the total resistance of the circuit?
"http://www.tpub.com/neets/book1/chapter3/1-26.htm" This site explains how to calculate the resistance, but it decreases the resistance when you add more.
If their is more bulbs in a circuit does the resistance increase?
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).
What happens in a series circuit if the resistance is halved?
If you add a second resistor, the resistance of series circuit will increase.
How are light bulbs efficiency increased?
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.
When you add resistors that are in a series to a ciruit?
You raise the total resistance by that amount if added in series to a circuit. If you add them in parallel to a circuit then that total resistance will be less than the total of the added circuit.
