Question

1. a) Deduce ohm's law from the expression of drift velocity. b) Calculate the value of capacitance of capacitor "C" in the circuit diagram, if the equivalent capacitance of the circuit is 1 micro farad.

Answer 1

Answer:

In the given figure, capacitors C

1

,C

2

andC

3

are connected in parallel. The same potential is applied across all the three capacitors. Let Q

1

,Q

2

andQ

3

are charges on the three plates of capacitors such that

Q

1

=C

1

V

Q

2

=C

2

V

Q

3

=C

3

V

The total charge stored is Q=Q

1

+Q

2

+Q

3

and equivalent capacitance is C

eq

=

V

Q

So,

C

eq

=

V

Q

1

+Q

2

+Q

3

=

V

Q

1

+

V

Q

2

+

V

Q

3

C

eq

=C

1

+C

2

+C

3