In a bid to get the basic concept behind capacitors [ I'm weak in this section of electricity and magnetism [17]] , i'm posting a self-made question.CAN ANYONE PLEASE ANSWER TO THESE 3 QUESTIONS :
Question : In all the given questions [a,b,c] , FIND THE CHARGE FLOWING FROM THE CHARGED CAPACITOR TO THE UNCHARGED ONE.
[In [c] , an isolated capacitor is given ].
Please give atleast the steps / concepts used
1in [a],
since it is like the first option in highly conceptual question u asked next, it is the same
answer. No charge will flow . I have also given its reason in that question
in b,
since it is connected in parallel,both will have same pd across it.Let it be V.
let the new charges be q1 and q2.
q1c1 = q2c2 {from c = q/v}
also applying conservation of charge q1 + q2 = q
solving the 2 eq →
q1 =qc1c1 + c2 q2 = qc2C1 + C2
1how CAN YOU SAY WHETHER IT IS PARALLEL OR SERIES WHEN NO BATTERY IS CONNECTED YAAR ?? [2]
1in c,
this can be done the same way as b
here also they are at a common potential say V.
let the new charges be q1 and q2,
here also q1 + q2 = q
q1 = qc1c1 + c2 q2 = qc2c1 + c2
in case of a sphere C = 4(pi)(epsilon)(radius)
substituting this in eq for q1 , q2 (4(pi)(epsilon) gets canceled from numerator and denominator)
q1 = qR1R1 + R2 q2 = qR2R1 + R2
for concept try : http://ocw.mit.edu/OcwWeb/Physics/8-02Electricity-and-MagnetismSpring2002/VideoAndCaptions/detail/embed07.htm
1u r right there is no series ,parallel
just to show that they have same pd across them.
1ARREY YAAAR...HOW CAN YOU SAY THAT 2 THINGS ARE PARALLEL / SERIES WHEN NO EMF SOURCE IS CONNECTED....ONLY WHEN A CELL IUS CONNECTED THINGS LIKE COMMON POTENTIAL OR EQUAL CHARGE OR EQUAL CURRENT CAN BE SPOKEN OF..THEN HOW DO YOU JUSTIFY IT ???????????????????????????????!
1OK there is no series parallel in this case
take the point K (switch in this case ) .it has only 1 potential and it is common to -ve plate of both capacitors . so -ve plate of both capacitors are at same potential.
now take a point on the wire near where u have written b ( between +ve plates of both capacitors ) .this single point has only 1 potential so both +ve plates have only 1 potential
so the capacitors have the same potential difference across them .