Mutual Inductance - Electromagnetic Induction Video Lecture - EmSAT Achieve

hello friends this video on
electromagnetic induction part 17 is
brought to you by exam fee or form no
more pure from exam please make sure
that you have watched all the videos to
the part 16 before going ahead with this
one oh it is time that I introduced you
to mutual inductance now what is natural
inductance in case of mutual inductance
we will not talk about one foil here I
have two coils so in one foil you will
pass some current through that coil
because of that current because of the
current when the current passes through
that coil the due to the increase of
current there is a change in flux
because of that change in flux
there will be a current induced in the
neighboring point right so that is the
concept of mutual induction so in later
suppose this is the scenario of mutual
induction where you have coil 1 this is
coil 1 which is connected to a battery
and this is coil 2 which is just
connected to a galvanometer that means
coil 2 has no source of current but it
just has a galvanometer to detect the
presence of current in this coil so what
happens as soon as you switch on the key
of coil 1 current starts flowing through
this pipe that means the current starts
to increase from 0 to some value I now
as current increases through this coil
flux linked with the coil also increases
as a result flux of coil 2 also
increases now since there is a change of
flux of coil 2 occurring and EMF is
induced in coil 2 because of this
induced EMF there is a current which is
induced in coil 2 now this current
induced in coil 2 will be such that it
opposed the current increase in coil 1
because the increase of current in coil
1 was the cause of current induction in
coil 2 so if the induced current in this
coil will try to oppose the increase of
current in coil 1 so what happened here
you switch on the key so current flows
in coil one as a result as soon as
current flows in coil one current
increases from 0 to some value I so what
happens flux linked also increases as a
result flux of coil 2 also increases as
a result EMF induced in coil - now when
EMF is induced in coil to cut induced
current is seen in - in coil 2 now this
induced current opposes increase of
current in 1 this is the entire
phenomenon of mutual induction so how do
I write it mathematically we can say
that the flux change in coil 2 is
directly proportional to the current
which is flowing in coil 1 because as
the current flowing in coil 1 is
changing the flux change in coil 2 will
also change so we can write that the
flux change of coil 2 can be written as
some constant of proportionality into
the current which is flowing in coil 1
so this constant of proportionality is
known as mutual inductance in this case
you can see that the flux change of one
coil is varying proportionally with the
current in the neighboring point right
therefore what will be the induced EMF
induced EMF in coil 2 will be e is equal
to minus D Phi 4 coil 2 divided by DT so
we can write it from this expression we
can write it as minus D by DT of M I
where I is the current flowing in coil 1
so we can write E is equal to minus M D
I by DT where what is e e is the EMF
induced in coil 2 and I is the current
which is flowing through coil 1 right so
this is the phenomenon of mutual
induction and this is your mutual
inductance so in this case also the
value of mutual inductance depends upon
geometry of the two coils distance
between the coils and orientation of the
coils you will come to know all these
things when we derive an expression for
mutual inductance like you saw that how
we derived the derivate if we derive the
expression for self inductance and we
saw that the self inductance is
dependent on the number of turns on each
coil it is dependent on the value of U
which depends on the nature of material
of the coils right similarly when you
find out the value for the mutual
inductance you will see that this also
depends upon the geometry of both the
coils it depends upon the distance
between the coils and it also depends
upon the orientation of the coils thank
you please visit exam fee or comm to
watch free educational videos try 3
online tests get the best quality study
materials study from the best tutors and
mentors and much more thank you once
again