Capacitors in Series

Let three capacitors  C1 , C2 and C3  be connected in series as shown. The capacitor plates are named  A,B,C,D,E and F.

Capacitors in series circuit

When a battery is connected to the series combination, the negative terminal of the battery supplies a  –ve charge to plate F. Simultaneously, the positive terminal of the battery sucks negative charge from plate A and therefore creating a +ve charge on plate A. Thus, charge is conserved.So now plate A has a +ve charge and plate F has a –ve charge as shown.
Capacitors in series charging

Positive charge on plate A attracts electrons of the BC plate combination towards plate B. Therefore, a –ve charge and a +ve charge appears on plate B and plate C respectively as shown. The BC plate combination which is isolated from everything else remains neutral as a whole and only redistribution of charge takes place.

Capacitors in series


Similarly, electrons of the DE plate combination drift towards plate D , thus giving plate  D  a –ve charge and plate  E  a +ve charge  as shown. Again, the DE plate combination as a whole remains neutral.


capacitors in series


The above process continues till capacitors get fully charged.

You may have observed that any charge sent/sucked by the battery to /from the end plates i.e Plates A and F  will induce an equal amount of charge in all the plates in between i.e in Plates B,C,D and E . 
Therefore, in series combination of capacitors, each capacitor has equal charge for any value of capacitances.  

As  Q=CV  for a capacitor

capacitors in series

To summarise :-

  1.  All capacitors in series store equal charge for any value of capacitances.
  2.  Equivalent capacitance value is smaller than all the individual capacitance values.
  3.  Equivalent capacitance value is given by  
         capacitors in series
  4.  As  Q=same  for all the capacitors connected in series therefore,
        
         capacitors in series
          i.e  lower the capacitance value higher the potential difference across              it and vice-versa.


Related concepts :-
(1) Capacitors in Parallel
(2) Inductors in Parallel 
(3) Inductors in Series