Is A Light Bulb A Resistor?

Is A Light Bulb A Resistor
  • Author: Amanda Arnold
  • Posted On: September 5, 2021
  • Updated On: August 21, 2023

Undoubtedly, it’s impossible to light up your home without a light bulb. The light bulb was one of the greatest inventions, and we should appreciate our scientists for it. Not only in houses, but we use light bulbs almost everywhere for better vision or visibility.

Fortunately, it’s super easy to perform our tasks even the nights just because of the bulb. So, it is one of the most efficient things necessary for our regular lives.

Well, our main question is the light bulb a resistor? If you are also there for the answer to this question. We will try our best to share all the details about this fact. Anyhow, the light bulb is not a standard resistor. However, it behaves like a resistor because of the limited flow of electrons.

Indeed, the electrons also face resistance when they pass through the bulb and form energy because of it. If we see logically, it’s a fact that the light bulb is a resistor. For more details, let’s discuss this fact briefly:

Light Bulb Is A Resistor, But Not Exactly

Before understanding the bulb mechanism, we have to know about a resistor. So, we can understand why the light bulb is not exactly a resistor. However, it acts as a resistor. Resistors offer resistance against the flow of electrons. So, one can limit the current flow in the appliances and electrical circuits.

Light Bulb Is A Resistor.

But you have to know more about this fact. For this, you have to know about Ohm’s law. So you can understand the proper flow of electric current and electrons in the circuits.

For this, nothing would be better than following Ohm’s formula to calculate the proper flow of electrons in a circuit or electric bulb.

Krystal from WiringSolver explained to us that if there is an increase in the voltage, the current will surely increase but linearly in the circuit. The resistor holds its value appropriately regardless of the current flow or ratio in the circuit. If the resistor is non-ohmic, it doesn’t follow the increase or decrease in the voltage accordingly.

However, the overall resistance depends on the type of material and the amount of current passing through the material.

When Do The Light Bulb Act Like A Resistor?

After a complete discussion about the resistor in the above paragraph, it would be easy to know about the Ohmic and non-Ohmic resistors or bulbs. Undoubtedly, the light bulb is not a standard resistor. But only act as a resistor in a few cases.

Light Bulb Act Like A Resistor.

Because of the presence of filaments, most bulbs form some resistance when the current passes through. The bulb transforms this resistance into heat and energy to light it up. If the bulb is made up of incandescent, it will surely act as a resistor because of its higher resistance.

However, the rate of resistance and heat will increase in the incandescent bulbs in the case of higher voltages. Applying a greater voltage to the light bulb will create more heat and energy with lower resistance.

On the other hand, the bulb acts as a resistor because of a coil in it. In the case of wounds, the resistance will increase in the coil.

Do We Consider The Light Bulb As A Resistor?

Of course, yes! According to Ohm’s law, we can use the light bulb as a resistor in electric circuits. According to the above discussion, the light bulb is not a conventional resistor. However, we can use it in electric circuits instead of resistors to control the current overflow.

Consider The Light Bulb As A Resistor

Excitingly! We can perform the same job with a light bulb instead of a resistor. This way, we can light up the bulb with more heat and energy than waste it.

On the other hand, you have to avoid using the light bulb in a circuit as a resistor. The reason is that the current flow will not remain constant in the bulb as a resistor.

So it might be harmful to your circuit. Consequently, the resistance of the light bulb also varies according to the varying heat or voltage. That’s why a light bulb is not an ideal option as a resistor. Now, it’s up to you to use the circuit bulb or a resistor to control the voltage variations.

Replace The Light Bulb Resistor With an LED

You can use the light bulb as a resistor in the circuit but at your own risk. The reason is that the light bulb resistor behaves differently in different cases and scenarios. So, using a bulb for a large circuit as a resisting item is not a safe option.

 Replace The Light Bulb Resistor With an LED.

For this, nothing would be a better option than replacing the light bulb with an LED. No doubt, the resisting power of an LED is lower than a bulb. But it doesn’t damage the circuit in case of fluctuation.

Ideally, the heat dissipation level in the LED is the same as in the bulb. So, it would be the best and the most efficient alternative to the bulb in the electric circuit.

When Does The Electrical Resistance Of A Light Bulb Decrease?

Since the majority of the materials used to make a light bulb’s filaments have a negative temperature coefficient of resistance. So, as the light bulb filament warms up, its electrical resistance reduces. The current running through the filament significantly impacts how hot it becomes.

Resistance decreases as temperature increases and current flow increases. Resistance rises when the temperature drops with decreasing current, and vice versa.

Which Type of Light Bulb Is A Suitable Resistor?

If the light bulb consists of Tungsten material, it will act as a resistor. However, using traditional bulbs in the circuit is unsuitable as resistors. The reason is that those bulbs don’t include the Tungsten material. They are made up of carbon paper and Bamboo.

Type of Light Bulb Is A Suitable Resistor

If you use these conventional bulbs in the circuits, do it at your own risk.

Moreover, the presence of Carbon material in the bulb creates a negative temperature coefficient of resistance. In this case, the temperature increases, but the resistance decreases. Unfortunately, this sudden decrease in resistance may cause power fluctuation and harm the circuit.

Frequently Asked Questions

How to measure the resistance of a bulb?

Theoretically, the resistance of the lightbulb can be calculated using the formula R=V2/P R = V 2 / P. Using a multimeter, measure the resistance of such a bulb and compare the result to the value predicted theoretically. The findings shed light on how resistance varies with temperature.

How to change the resistance of an electric circuit?

Resistance rises in intensity. Adding bulbs to a series circuit raises the circuit resistance.

Why does resistance important for light bulbs?

Electrical energy is wasted along the way due to resistance, which results in some of it converting to heat. However, resistance makes using electricity for heat and light possible. Resistance is responsible for producing the heat from electric heaters and the light we receive from light bulbs.

Final Verdict

In short, if you want to use the bulb as a resistor in an electric circuit, do it after knowing the material type of bulb. If you are using conventional bulbs as resistors, it is not safe for the circuit. However, if Tungsten is present in the bulb, use it as a resistor.

Moreover, the bulb’s performance as a resistor depends on the number of electrons and the voltage passing through it.

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Author: Amanda Arnold

Amanda has been working with ConstructionHow since 2021. Her experience spans over 5 years in the creative niche such as home decor and trends, landscaping, renovations, and custom architectural values. As a home designer expert, she has a keen eye for the latest home improvement trends with accurate facts that readers find impossible to ignore. Being invested in home-building trends is how she has gained her lucrative expertise exploring more to bring a positive ambiance for all homeowners (and even tenants!). Currently, she lives in a beautiful beach home, a source of fascination for her.

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