Electromagnetism and Domestic Electric Circuits, Lecture notes of Electromagnetic Engineering

Download Electromagnetism and Domestic Electric Circuits and more Lecture notes Electromagnetic Engineering in PDF only on Docsity!

tism

By: Vatsal X D

Oersted Experiment

 Hans Christian Oersted, one of the leading scientists of the 19th century, played a crucial role in understanding electromagnetism.  In 1820 he accidentally discovered that a compass needle got deflected when an electric current passed through a metallic wire placed nearby.  Through this observation Oersted showed that electricity and magnetism were related phenomena.

Magnetic field lines

 The magnets exert their influence in the surroundings,this is called magnet field  Magnetic field is a quantity that has both direction and magnitude.  The direction of the magnetic field is taken to be the direction in which a north pole of the compass needle moves inside it.

Properties



Two Magnetic field lines never

intersect each other.



Magnetic field intensity is higher if

magnetic lines are closer.



The lateral pressure acting on

magnetic field lines between two

similar poles represents that they

repel each other.

Right hand thumb rule If the thumb is along the direction of current, wrapped fingers will show the direction of circular magnetic field lines.

Magnetic field in a

circular loop

S N

Anticlockwise: North Pole Clockwise: South Pole

Right hand rule



Hold out the right hand with the first

finger, second finger and thumb at

right angle to each other.



If forefinger represents the direction

of the line of force, the thumb points

in the direction of motion or applied

force, then second finger points in

the direction of the induced current.

 Alternating current ( AC ), is an electric current in which the flow of electric charge periodically reverses direction.

 Direct

Current,is

the flow of

electric

charge is

only in one

direction.

It is the current of magnitude varying with time  (^) It is the current of constant magnitude.

Solenoid



A solenoid is a coil of insulated or

enameled wire wound on a rod-

shaped form made of solid iron, solid

steel, or powdered iron.

Magnetic flux



Magnetic flux is the number of magnetic field

lines passing through a surface placed in a

magnetic field.



We show magnetic flux with the Greek

letter; Ф.

DC generator

 A Tesla coil is a resonant air core transformer system invented by inventor Nikola Tesla in the 1890’s.  Originally, Tesla coils were designed to broadcast electricity and signals wirelessly.  It is a form of induction coil for producing high-frequency alternating currents.

Tesla Coil

DOMESTIC ELECTRIC

CIRCUITS

FUSE

 An electrical device that can interrupt the flow of electrical current when it is overloaded  It is plainly a passive device which protects the circuit in the event of a large current. When this happens, the fuse melts and the circuit breaks.  Hence it protects appliances from damage due to high current