Resistor Series Circuit

Resistors in Series 

An electrical circuit is one with all the hundreds during a Row. there’s only 1 path for the electricity to flow. If this circuit was a string of sunshine bulbs, and one blew out, the remaining bulbs would shut down.

Series Circuits Defined

Two elements area unit serial if they share a typical node and if a similar current flows through them. Here’s AN example circuit with 3 series resistors: 

There’s just one manner for this to flow within the higher than the circuit. ranging from the positive terminal of the battery, current flow can 1st encounter R1. From there this can flow straight to R2, then to R3, and at least back to the negative terminal of the battery. Note that there’s just one path for current to follow. These elements are serial.

Calculating Equivalent Resistances in Series Circuits

Here’s some info that will be of some additional sensible use to you. once we place resistors along like this, serial and parallel, we modify the manner current flows through them. for instance, if we’ve got a 10V provideacross a 10kΩ resistance, Ohm’s law says we’ve got 1mA of current flowing.

If we have a tendency to then place another 10kΩ resistance nonparallel with the primary and leave the provision unchanged, we’ve cut this in 0.5 as a result of the resistance is doubled.

In alternative words, there’s still only 1 path for current to require and that we simply created it even tougher for current to flow. what proportion harder? 10kΩ + 10kΩ = 20kΩ. And, that’s however we tend to calculate resistors asynchronous – simply add their values.

Series Resistor Equation

Rtotal = R1 + R2 + R3 + ….. Rn etc.

To put this equation more generally: the total resistance of N – some arbitrary number of – resistors is their total sum.

If 2 resistors or impedances nonparallel square measure unequal and of various values, then the entire or equivalent resistance, RT is capable the mathematical add of the 2 resistances. that’s capable R+ R2. If 3 or additional unequal (or equal) resistors square measure connected nonparallel then the equivalent resistance is: R+ R2R3 +…, etc.

The total resistance of a series circuit is equal to the sum of individual resistances

In the electrical circuit, you may got to calculate the whole resistance of the circuit so as to work out the electrical phenomenon. this can be done by adding up the individual values of every element asynchronous. In this example. we’ve got 3 resistors. To calculate the whole resistance we have a tendency to use the formula:

RT = R1 + R2 + R3

2 + 2 + 3 = 7 Ohms

R total is 7 Ohms

Now with these 2 rule, we will learn the way to calculate the electrical phenomenon of a circuit. 
Remember from Ohms Law I = V / R. currently we are going to modify this slightly and say I = V / R total.

Let’s follow our example figure :

RT = R1 + R2 + R3

RT = 7 Ohms

I = V / RT

I = 12V / 7 Ohms

I = 1.7 Amp

If we had the amperage already and wanted to know the voltage, we can use Ohm’s Law as well.

V = I x R total

V = 1.7 A x 7 Ohms

V = 12 V

“Voltage Drops”

Before we tend to go to any extent further let’s outline what a “voltage drop” is. A drop is that the quantity voltage lowers once crossing apart from the negative aspect to the positive aspect a very electrical circuit. If you placed a multimeter across an electrical device, the drop would be the number of voltage you’rereading. this is often pictured with the red arrow within the diagram.

Say a battery is supplying 12 volts to a circuit of two resistors; each having a value of 5 Ohms. According to the previous rules we figure out the total resistance.

RT = R1 + R2 = 5 = 5 = 10 Ohms

Next, we calculate the amperage in the circuit:

I = V / RT = 12V / 10 Ohms = 1.2 Amp

Now that we know the amperage for the circuit (remember the amperage does not change in a series circuit) we can calculate what the voltage drops across each resistor is using Ohm’s Law (V = I x R).

V1 = 1.2A x 5 Ohms = 6 V

V2 = 1.2A x 5 Ohms = 6V

Voltage applied to a series circuit is equal to the sum of the individual voltage drops

This simply means that the voltage drops have to add up to the voltage coming from the battey or batteries.

V total = V1 + V2 + V3 …

In our example above, this means that

6V + 6V = 12V.