what is Induced e.m.f:
Generally induced e.m.f is nothing but whenever current carrying conductor placed in the magnetic field that conductor get induced and produce the electro magnetic force. there are two types of induced e.m.f is there. they are given below, ,
i) Dynamically induced e.m.f
ii) statically induced e.m.f
Dynamically induced e.m.f:-
We can see from the figure that a conductor A is lied within a uniform magnetic field whose flux density is a uniform magnetic field . and the flux density is B wb 3. In this fig. the movement of the conductor is shown by arrow line. When the conductor A cuts across at right angles to the flux.
Let, ‘l’= Length of the conductor lying within the field. And it moves a distance dx in time dt, So, the area swept by the conductor is =ldx.
Hence, flux cut by the conductor = l.dx X B,
Change in Flux = B.l.dx weber,
Time= dt second
this is called dynamically induced emf.
If the conductor (A) moves at an angle θ with the direction of flux which is shown in (b).
An example, the generator works on the production of dynamically induced e.m.f in the conductors.
Statically induced E.m.f:-
Statically induced e.m.f is two types which are –
i) Mutually-induced e.m.f.
ii) Self-induced e.m.f.
Mutually induced e.m.f:-
Mutually induced e.m.f occurs in between two coils. Let, A & B are two coils which are placed close to each other. if coil A is connected to dc battery and single control switch and further its connected to variable rheostat. and coil B is connected to voltmeter. if the switch in coil A is closed then current is flow through the coil A and produced the magnetic flux according to faradays law of induction the nearest coil B also get induced and produce the flux. if the flux change in coil A is impact the flux change in coil B. That coil B induced its called mutual induced emf.
In the above example, there is no movement of any conductor, the flux variation being brought about by variation in current strength Only. Such an e.m.f induced in one coil by influence of the other coil is called mutually induced e.m.f.
you can see the diagram above will show the self induced emf. according to this diagram self induced emf is nothing but when the switch is close the current will flow through the coil and produced the magnetic flux. if you adjust that variable resistance then flux will be change. this produced emf its called self induced emf.