Calculation of Kirchhoff Voltage law

In previous post we look about theory of kirchhoff voltage and current law. Now we going to learn how to calculate kirchhoff voltage with example of a circuit diagram. It's easy to understand and you need to think clearly to do calculation on the circuit.

KIRCHHOFF VOLTAGE LAW : The sum of the voltage drops around any closed loop is zero.

Based on the circuit diagram below we going to calculate the value of voltage and current.

Now on the circuit diagram you will notice that there's no value of voltage and current on each resistor. Only value of resistance is present. In order to calculate the value of voltage and current we need to split this circuit into two loop.

 Now we going to use Kirchhoff current law to determine the node for that circuit so:

1) I1+ I2-I3 = 0 

2) I1+I2= I3

Therefore for kirchhoff voltage law :
                                    
                                 Loop 1 : VR1+VR2-VS= 0
                                               VR1+VR2=VS  
                                 
                                 Loop 2 : VR3+VR2-VS =0
                                               VR3 + VR2 = VS
To find current for each resistor we need to use ohms law to determined the value of current for each resistor. So the equation will be :

V= IXR

For Loop 1 : [I1X6Ω]+ [I3X4Ω] = 28V 
                     I1 =28V/6
                         =4.7A
                     
                     I3 = 28V\4
                         = 7A 

For Loop 2 : [I2X12Ω] = 7V
                    I2 = 7V\12
                        = 0.58A
                    
                    I3 = 7V/4
                        = 1.75A

Now we get all the value of current, so it's easy to calculate the value of voltage each resistor.  

VR1 = 4.7A X 6Ω = 28.2V
VR2 = 7A X 4Ω = 28V
VR3 = 0.58A X 12Ω = 6.96V
VR2 = 1.75A X 4Ω = 7V loop 2    

Now we get all the value of voltage of each resistor. Now we going to total all the voltage,current and resistor. To calculate the total value of voltage,current and resistor, we need to calculate separately. So teach loop will be in series circuit and you need to apply series circuit formula.

 
Voltage Loop 1 : V= VR1+VR2= [28.2V+28V=56.2V]
Resistance loop 1 : R= R1+R3= [ 6Ω+4Ω=10Ω]
Total Current loop 1 : I=V/R =[56.2V/10=5.62A] 
The total voltage in loop 1 is 29.95V this is because, the current is drop in R1 and increase in R2.

Voltage Loop 2 :  V= VR3+VR2= [6.96V+7V=13.96V]
Total Resistance loop 2 : R= R2+R3= [ 4Ω+12Ω=16Ω] 
Total Current loop 2 :  I=V/R =[13.96/16=0.87A] 
The total voltage in loop 2 is 13.96V this is because, the current is drop in R3 and decrease and increase in R2.

WELL LEARN HOW TO CALCULATE KIRCHHOFF VOLTAGE LAW WITH OHMS LAW. IN NEXT POST WE GOING TO LEARN CALCULATION OF KIRCHHOFF CURRENT LAW.TILL THEN KEEP TRY AND MASTER THE LAW OF ELECTRICITY.