Voltage Divider Rule For The Series Parallel Circuit With Examples

Voltage divider rules states that Voltage divides in series circuit only. In parallel circuit voltage remains same. All of the loads are connected parallelly across voltage source so that loads have two common points with source positive and negative terminals. When the circuit element connected parallelly across source they get same voltage so that all of the circuit element can use their full power such as a 100 Watt bulb will emit full light if it connects in parallel with source. If you connect some bulb in series the source voltage divides among them so that they can not show their full power all the bulb will emit with lower light when series connection. In our daily life voltage divider rule is the basic formula of voltage division where you need to divide voltage use voltage divider formula. Parallel circuit same voltage series circuit voltage division. All the connection in household are in parallel as all the element fan, bulb, refrigerator, AC, TV, oven etc. are getting same voltage they are taking different current which they needed AC, oven takes much current than fan, bulb, refrigerator. If you connect all the these element in series may be the bulb not glow because maximum drop will occur in AC & oven the bulb will get a very few charge if it connects at the end of the circuit.

Considering above circuit three resistors are connected parallelly with source of 220V. Question is what the drop voltage is across three resistors 10, 20 and 30 ohms? The answer is 220V of course. Because three resistor’s positive terminals are connected with the source positive terminal and negative terminals are connected with source negative terminal so voltage remains same at parallel circuit.

In our household the total circuit is connected parallelly so all the electronic devices get same voltage and you can check voltage via digital multimeter. If we connect some same power bulbs in series, one bulb will give shining light, second bulb will give less light and third one will less more light because here voltage divides. TV, fridge, bulb, fan etc all are connected in parallel and they take current according to their requirement. Series connection means voltage division and parallel connection means current division.

If we connect the same resistors in series then voltage will not same it will divide according to resistor value. We know current flows positive terminal to negative terminal. It is the concept of electrical engineering. Science concept is current flows from negative to positive terminal. Actually positive charge has more mass than electron so it does not move; electron moves and comes to positive charge to neutral it. So we can say 30ohm resistance has more voltage than other two resistors, then 20ohms voltage and 10ohm resistor gets less voltage than other two resistors.

Voltage Divider Formula

Voltage divider rule is that rule if a series circuit has more than one resistor; the voltage across of each resistor is the ratio of resistor value multiplied with voltage source to total resistance value.

Let us consider above circuit there is three resistances. We have to find out each resistance voltage. Using voltage divider rule,

It is also known as voltage formula.

Example of Voltage Divider Rule:

For example of voltage divider rule now we will solve the simple circuit has 6V source and 200 ohm, 100 ohm resistance. We will find voltage drop across each resistance.

Applying formula,

Voltage across 100Ω resistance V₁ = (100*6)/(200+100) = 2V

Voltage across 200Ω resistance V₂ = (200*6)/(200+100) = 4V

Current Divider Rule

Series circuit same current, parallel circuit current division. Current remains same in series circuit. It only divides in parallel circuit.

Considering above circuit there are three resistance R₁ , R₂ , R₃ connected in series having same current I. They are experiencing same current although voltage is different.

We know current is flow of charge per unit time through conductor. Equation of current is I = Q/t .

Let us consider the conductor of this circuit carries 100 C charges per second. Here first resistance prevents flow of charge rate then second resistance gets less charge than first one and third one gets more less than first two resistances. If we remove first resistance, second resistance will get same flow rate which first one experienced, if we remove first and second resistance third one will experience same flow of charge which first one observed. In a word we can say flow of charge remains constant either any of resistance is added or removed. So flow of current remains same for series circuit. Current divides parallelly.

We see here in figure I current are coming and divided into I₁ and I₂ via two resistance.

The formula of current divider rule is

The current of each resistor is the ratio of multiplication of total current and opposite resistor value with total resistance.

In our household current divider rule is applied. We use different types of electronic devices and machine. Some of them need small current some of them need huge current. When they are connected in parallel there is no clash between them. No one effects others power taking system. They take current as required. If they are in series then they will not independent. As parallel connection all are independent and takes current as need. Current divider rule is only applicable for two resistors when many resistors are connected in parallel some other methods will be applied to find each current value.