Electromagnetism

Electromagnetism

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.

Direction of magnetic field

Right hand palm Rule First make the thumb and fingers of the

right hand perpendicular to each other and put the thumb along the wire in the direction of the current and fingers point towards the point of observation

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 NAnticlockwise:

North PoleClockwise:South Pole

Left hand Rule Hold out your left hand with forefinger,

second finger and thumb at right angle to one another. If the fore finger represents the direction of the field and the second finger that of the current, then

thumb gives the direction of the force.

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.

AC generator

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

In a Domestic Circuit, A red wire is the Live Wire because it carries current.

The neutral coloured  Blue  is the return  wire .

The last wire is the Earth wire which is of green color.

Types of wires

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

Thank YouMade by:Vatsal

Class:X D