Have you ever wondered why all light bulbs are not created equal? Why do some resistors work better than others? The truth is that it all has to do with the material used, and in this case, the resistance of each material has an impact on the quality of your light bulb, as well as its overall lifespan. Check out this article to learn more about these materials and how they affect your light bulb’s operation!
Why Is Wire Resistance Important?
Every material used to make a light bulb has a resistance rating, which can determine how bright your light is, how efficient it is, and even its lifespan.
When designing a circuit you will want to choose wire with a resistance that gives you enough power for your circuit but also doesn’t waste too much energy as heat.
Choosing resistors of different sizes is important when building circuits! For example, if you are powering a 5-volt LED from a 9-volt battery, then the resistor should be at least 4.7 ohms (according to Ohm’s Law). If the resistor is too small or large in this situation, then either the LED won’t work or it will become so hot that it burns out quickly.
Remember: Resistors can be used not only in circuits powering LEDs but also in other places like audio amplifiers and dimmer switches!
Resistor Basics
Resistors are electrical components that cause a specific amount of resistance in a circuit, measured in ohms. Essentially, resistors keep current from flowing freely through a device (such as an LED light bulb).
It is important to note that voltage and current flow at different rates, and some devices need to be supplied with power at a certain rate (for example, electric motors). By slowing down or limiting current flow through an electrical component, you can regulate these speed/power issues—and as such, resistors are incredibly important for safety and maintaining functional electronic devices.
Resistors in Series and Parallel
Resistors can be connected in both series and parallel circuits (see figure below). However, when considering equivalent resistance, they are combined differently:
Resistors in Parallel: In a parallel circuit, all resistors have equal resistances.
Resistors in Series: In a series circuit, R is calculated by adding up each resistor’s value to find total resistance.
Example Calculations: Let’s try some simple calculations based on what we know so far.
Q: How much current flows through three identical resistors connected in parallel with a voltage of 4 V across them? I = 4 V / (3 Ω) = 1 A Find total resistance for two 2 Ω and one 3 Ω resistor connected in series with a voltage of 9 V across them?
V = 9 V
R = R1 + R2 + R3
R= ((2 Ω)*(4 V))+(1 Ω*(6 V))+((3 Ω)*(9 V)) =(16 V)+(6 V)+((27 Ω)*(18 V))=(31 Ω)
The same calculation done as if the resistors were wired in parallel would result in 3 Ω, which may not seem correct at first. But after applying equivalent technique, you can obtain the correct results.
How to Identify Resistor Values
All resistors have colored bands printed on them. The first two colors indicate what order they’re in: brown-black-gold and blue-violet-red are both band 1,while violet-blue is band 2. For example, a resistor with brown and black stripes would be a 1st order resistor; one with brown and red stripes would be 2nd order.
The third color corresponds to the value of the resistor. If it’s orange, the resistance is between 10 and 100 ohms (1st order); if it’s yellow, the resistance falls between 100 and 1000 ohms (2nd order). If it’s silver or gold, you’re looking at an extremely high-value resistor—the only ones you’ll find these days are in ballast boxes for fluorescent lights. If there’s no third color band at all,then the resistance can’t be measured without a voltmeter.
Should I Use Fixed Resistors or Variable Resistors in My Projects?
This is a common question, and one with several factors to consider. If you’re building a circuit that requires resistance that needs to be in a certain range (for example, if you’re using it as part of an oscillator), then you’ll need to build something with a variable resistor and can search for a potentiometer or rheostat to meet your project’s needs.
But if you need resistance, regardless of value or use, then all you really need is something with 2 ohm value; after all, resistors are resistors! In fact, electronics hobbyists will often use wattage-rated light bulbs for simple low value burner circuits because they’re cheap and easily replaceable.
What’s the Best Way to Learn More About Resistors?
Since resistors are used to create circuits, it’s important to understand how they work and how different resistances affect your circuit. One of our favorite resources is a Resistors Tutorial from SparkFun Electronics . This short tutorial is made up of a series of videos that walk you through what resistors are, their applications, and most importantly, their formulas.
You’ll learn everything you need to know about these components in a fun and easy way! Plus, if you haven’t had enough yet and want more background on these components, check out SparkFun’s full Learn Guide for Resistors. There you’ll find an even more in-depth look at electronic components with fun activities along the way!
Conclusion
As you can see from all of the calculations, it doesn’t matter whether a light bulb is 2.9 ohms or 3 ohms (for example). Whatever its resistance, there are ways to make sure that it is within safety margins so as not to shock anyone or cause fires.
Some stores sell light bulbs with lower resistance ratings, but they include a warning on the package stating that these bulbs should only be used in lamps without metal shades because these bulbs could overheat and cause fires in typical light fixtures due to voltage fluctuations inherent in many household electricity systems; using them properly can ensure your lights are safe and last longer as well!
Leave a Reply