What do you mean by back EMF?
Counter-electromotive force
What is the importance of back EMF?
The significance of Back EMF Back emf is very significant in the working of a dc motor. The presence of back emf makes the d.c. motor a self-regulating machine i.e., it makes the motor to draw as much armature current as is just sufficient to develop the torque required by the load.
How is EMF generated in a transformer?
A transformer consists of two electrically isolated coils and operates on Faraday’s principal of “mutual induction”, in which an EMF is induced in the transformers secondary coil by the magnetic flux generated by the voltages and currents flowing in the primary coil winding.
What are the effects of a transformer?
The transformer effect, or mutual induction, is one of the processes by which an electromotive force (e.m.f.) is induced. In a transformer, a changing electric current in a primary coil creates a changing magnetic field that induces a current in a secondary coil.
What is eddy current effect?
Eddy currents (also called Foucault’s currents) are loops of electrical current induced within conductors by a changing magnetic field in the conductor according to Faraday’s law of induction. This effect is employed in eddy current brakes which are used to stop rotating power tools quickly when they are turned off.
Where are eddy currents used?
The minor application areas where eddy currents are utilized include use in energy meters, automobile speedometers, induction alternating current (AC) motors, free-fall devices, as a way of detecting coins in vending machines, to increase temperatures uniformly in induction furnaces, and in proximity/displacement …
What are eddy currents losses?
Eddy current loss is conductive I2R loss produced by circulating currents induced in response to AC flux linkage, flowing against the internal resistance of the core.