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ELECTROMAGNETISMELECTROMAGNETISM

ELECTROMAGNETISM ????ELECTROMAGNETISM ??????

ELECTROMAGNETISMELECTROMAGNETISM

THE BRANCH OF PHYSICS THAT DEALS THE BRANCH OF PHYSICS THAT DEALS WITH THE RELATIONSHIP BETWEEN WITH THE RELATIONSHIP BETWEEN

ELECTRICITY & MAGNETISMELECTRICITY & MAGNETISM

MAGNETIC PHENOMENONMAGNETIC PHENOMENON

ELECTROMAGNETISMELECTROMAGNETISMDAVY’S EXPERIMENTDAVY’S EXPERIMENT

OERSTED’S EXPERIMENTOERSTED’S EXPERIMENT

                                                   

ANY CHARGE IN MOTION ANY CHARGE IN MOTION CREATES MAGNETIC FIELDCREATES MAGNETIC FIELD

MOVING ELECTRONS MOVING ELECTRONS INDUCE MAGNETIC FIELDINDUCE MAGNETIC FIELD

DETERMINING THE DETERMINING THE DIRECTION OF THE DIRECTION OF THE

MAGNETIC FIELD AROUND MAGNETIC FIELD AROUND CURRENT CARRYING CURRENT CARRYING

CONDUCTORCONDUCTORTHUMB-DIRECTION OF ELECTRONS

FLOWFINGERS—MAGNETIC FLUX LINES

                                                           

COIL OF WIRE IS CALLED COIL OF WIRE IS CALLED HELIXHELIX

COIL OF WIRE CARRYING COIL OF WIRE CARRYING ELECTRICAL CURRENT IS ELECTRICAL CURRENT IS

CALLED SOLENOIDCALLED SOLENOID

SOLENOID’S MAGNETIC SOLENOID’S MAGNETIC FIELDFIELD

ELECTROMAGNET= ELECTROMAGNET= SOLENOID + IRON CORESOLENOID + IRON CORE

ELECTROMAGNETELECTROMAGNET

ELECTROMAGNET vs SOLENOIDELECTROMAGNET vs SOLENOID

                                                                              

ELECTROMAGNET SOLENOID

ELECTROMAGNETIC ELECTROMAGNETIC INDUCTION:INDUCTION:

AN ELECTRIC CURRENT IS INDUCED IN AN ELECTRIC CURRENT IS INDUCED IN IN A CIRCUIT IF SOME PART OF THIS IN A CIRCUIT IF SOME PART OF THIS

CIRCUIT IS IN A CHANGING MAGNETIC CIRCUIT IS IN A CHANGING MAGNETIC FIELDFIELD

E.M. INDUCTIONE.M. INDUCTION

STATIONARY CONDUCTOR + MOVING MAGNET

STATIONARY MAGNET + MOVING CONDUCTOR

ELECTROMAGNET WITH A/C CURRENT + STATIONARY CONDUCTOR

STATIONARY MAGNETSTATIONARY MAGNET

                             

MOVING MAGNETMOVING MAGNET

MOVING MAGNETMOVING MAGNET

ELECTROMAGNET WITH ELECTROMAGNET WITH A/C A/C

METAL DETECTORMETAL DETECTOR

FARADAY’S LAW FARADAY’S LAW

MAGNITUDE OF INDUCED CURRENT MAGNITUDE OF INDUCED CURRENT DEPENDS ONDEPENDS ON

THE STRENGTH OF MAG. FIELD THE VELOCITY OF MAG. FIELD THE ANGLE OF THE CONDUCTOR TO THE

MAG. FIELD THE NUMBER OF TURNS IN THE

CONDUCTOR

SPEEDSPEEDFAST –E.M.F FAST –E.M.F

ANGLEANGLEANGLE –E.M.ANGLE –E.M.

# OF COILS# OF COILS

STRONGER

WEAKER

LEFT HAND DYNAMO RULELEFT HAND DYNAMO RULE

N S

e

ELECTRON FLOW ELECTRON FLOW DIRECTIONDIRECTION

DIRECTION OF e

DIRECTION OF e

ELECTRIC GENERATORELECTRIC GENERATOR ( DYNAMO)—A DEVICE ( DYNAMO)—A DEVICE

THAT CONVERTS THAT CONVERTS MECHANICAL ENERGY TO MECHANICAL ENERGY TO ELECTRICAL ENERGY BY ELECTRICAL ENERGY BY

E.M. INDUCTIONE.M. INDUCTION

GENERATOR GENERATOR COMPONENTSCOMPONENTS

A POWERFUL MAGNETAN ARMATURE (WIRE LOOP)

                                                                                

GENERATORSGENERATORS

D/CA/C

D/C GENERATORD/C GENERATOR

COMMUTATOR RING

D/C POWER FROM D/C POWER FROM BATTERYBATTERY

I

TIME

A/C GENERATORA/C GENERATOR

                                    

A/C FREQUENCY IN THE US – 60 Hz

ELECTRIC MOTORELECTRIC MOTOR-A -A DEVICE THAT CONVERTS DEVICE THAT CONVERTS ELECTRICAL ENERGY TO ELECTRICAL ENERGY TO

MECHANICAL ENERGYMECHANICAL ENERGY

TYPES OF MOTORSTYPES OF MOTORS

D/C ( COMMUTATOR RING!!)A/C

D/C MOTORD/C MOTOR

A/C MOTORS A/C MOTORS

SYNCHRONOUS ( REVERSE OF

GENERATOR)

INDUCTION

INDUCTION MOTOR INDUCTION MOTOR ROTATES THE ANODE IN ROTATES THE ANODE IN

THE MODERN X-RAY TUBESTHE MODERN X-RAY TUBES

INDUCTION MOTORINDUCTION MOTOR

ROTORSTATOR

PRINCIPLE OF OPERATIONPRINCIPLE OF OPERATION

RIGHT HAND MOTOR RULERIGHT HAND MOTOR RULE

COMPARISON –COMPARISON –GENERATOR vs MOTORGENERATOR vs MOTOR