Series Circuit

Series circuit is which circuit there have only one path of flow electron /current . in this circuit the electrons flow in a counter -clockwise direction, from point 4 to point 3 to point 2 to point 1 and back ground to 4. current is same for all resistance but voltage drop is not same in this circuit.                                                                                                                                                                                                                                                                                                                                                                                                                                            
                      


it have only on path for flow electron so current always must same of each element . so we can write ,
Is=I1=I2=I3=..........................
Voltage drop by each element so
Vs = V1+V2+V3+....................
and the total resistance equation is
Rt=R1+R2+R3+........

Example: If R1=5 ohm, R2=10 ohm, R3=20 ohm and Vs=100 volt. find the total circuit current and each branch voltage drop. and total Power of this circuit.
Solution:
At first calculate total Resistance so ....
 Rt = R1+R2+R3
     = (5+10+20) ohm
     =35 ohm

then calculate source current. (source current = total current = Branch current)
Is =V / Rt
    =100 / 35
    = 2.858 Amp

calculation each branch voltage drop ......
 Vr1 = I*R1 = 2.858 * 5 = 14.29 Volt
 Vr2 = I*R2 = 2.858 *10 = 28.58 Volt
 Vr3 = I*R3 = 2.858 * 20 = 57.16 Volt

 We know from Kirchhoff''s law.......
                                                Rising voltage = Drop voltage 
                                                                100 = 100
                                                              Proved that here.

Total Power of this circuit is
 P  = VI
     = 100*2.858
     = 285.8 Watt.