Hello friends.
in this video we are going to see how to apply
series and parallel connections to
solve a problem to get a answer for equivalent
resistance between two points.
Sometimes the
problem of series and parallel connections
are not that straight forward so for that
we need to
have some other concepts in mind also.
so let us take an example at a simple circuit
like this
and if I ask what is RAB, the problem will
become very simple straight forward 6 + 3
+2 ,which is
nothing but 11, but hold on let&#39;s make
some modification to the circuit.
now the problem will not
remain that simple, because now there is some
connection between the 6 ohm and 3 ohm. at
the same time there is a connection between
this 3 ohm and 2 ohm, because of which we
cannot say 6 ohm, 3 ohm and 2 ohm are in series.
Hence we need to use some other concept
also.
As soon as I have connected this wire, since
there is no resistance in this wire, I can
say
this point A and this point A is same.
Since, there is no resistor or no element
connected
between these two points, So I can very well
say this point is also A. at the same time
B, this B
will remain same, because there&#39;s nothing
between these two points.
The same way from here
to here I have no element connected, it&#39;s
simply a wire I can say this point is also
B, If I take a
closed loop to the circuit there are only
two points present which are A and B all the
time for all
the resistors.
So I redraw the circuit, so more often this
condition may occur, if I redraw the
circuit I keep all the concepts intact, I
can say A and B are the only two points present
in the
circuit.
This 6 ohm is connected between A and B, this
3 ohm, connected between B &amp; A or you
can say A &amp; B.2 ohm connected between
A &amp; B .so keeping all the concepts intact,
I just redraw
the circuit, I&#39;ll get this circuit which
is very simple now because all of them are
in parallel .SO 3
parallel with 6, parallel with 2 and equivalent
is given as 1 upon RAB equals 1 upon R1 +
one
upon  R2 + 1 upon R3.
I just name with R1, R2,R3 ,which are nothing
but 1/3 + 1/6 + 1/2 and if
you solve further you will come to know RAB
value will be equal to 1 ohm, here one important
point, I would like to add to this problem.
I am having resistors connected in parallel
which are 3
in number if it is given state away two resistors
connected in parallel I could use a formula
multiplication of two resistor / 2 resistors
addition, but that is not applicable when
I&#39;m having
more than two resistors connected in parallel
for that case I have to use a basic formula
like this
.so this was another important problem that
we have discussed, where such a time we will
not
get series and parallel connections directly
given.
you need to apply some concept like this,
if
there is no element count between two points
of the circuit, those two points are nothing
but the
same points.
Further we will solve more numerical based
on this, thank you.
