ELECTROMAGNETICS - Intro&History

Electromagnetics

The branch of physics and engineering that studies electric and magnetic fields, their interactions, and how they influence charged particles and materials.

600 BCE – Thales of Miletus and Static Electricity

He observed that rubbing amber (a fossilized tree resin) with fur could attract lightweight objects, marking one of the earliest recorded observations of static electricity.

100 CE – Lodestones in Navigation

The Chinese and Romans discovered that certain naturally occurring minerals, called lodestones (magnetized iron ore), could attract iron and align themselves with the Earth's magnetic field.

1600s – William Gilbert

In De Magnete, he distinguished electricity from magnetism and proposed that Earth acts as a giant magnet.

1700s – Benjamin Franklin

His experiments, including the famous kite experiment, proved lightning is electricity. He introduced positive and negative charges, shaping modern electrostatics.

1800 – Alessandro Volta

Invented the Voltaic Pile, the first true battery, providing a steady electric current.

1820 – Hans Christian Ørsted

Discovered that electric currents generate magnetic fields, linking electricity and magnetism.

1827 – Georg Ohm

Formulated Ohm’s Law, defining the relationship between voltage, current, and resistance.

1831 – Michael Faraday (The Father of Electromagnetism) & Joseph Henry

Independently discovered electromagnetic induction, the principle `behind electric generators and transformers.

1861-1865 – James Clerk Maxwell

He unified electricity and magnetism into a single theory of electromagnetism.

1887 – Heinrich Hertz

Experimentally confirmed electromagnetic waves, proving Maxwell’s predictions and paving the way for wireless communication.

1890s – Tesla & Marconi

Pioneered wireless power and radio communication.

1905 – Einstein

Explained the photoelectric effect, leading to quantum mechanics.

1920s-1940s

Rapid advancements in radio, radar, and television technology.

1960s

Development of lasers, fiber optics, and microwave technology revolutionized communication and medical applications.

21st Century

Breakthroughs in 5G, quantum electrodynamics, MRI, and remote sensing continue to expand technological frontiers.

Scalar

A physical quantity that has only magnitude, with no direction.

Vector

A physical quantity that has both magnitude and direction.

Scalar Field

A function that assigns a scalar value to every point in space.

Vector Field

A function that assigns a vector to every point in space, representing both magnitude and direction.