Special Relativity Study Materials

Light cone (Image Credit: Wikimedia Commons)

Introduction:

One of the greatest triumphs of Maxwell's electromagnetic theory (c. 1864) was the explanation of light as an electromagnetic wave. But a question arises; Waves in what? In conformity with the mechanistic view of nature then prevailing, it seemed imperative to postulate the existence of a medium—the ether—which would serve as a carrier for these waves. This led to the most urgent physical problem of the time: the detection of the earth's motion through the ether.

One of the many experiments were devised for this purpose. Michelson and Morley (1887), looked for a directional variation in the velocity of light on Earth. Fizeau (1860), Mascart (1872), and later Lord Rayleigh (1902), looked for an expected effect of the earth's motion on the refractive index of certain dielectrics. And Trouton and Noble (1903) tried to detect an expected tendency of a charged plate capacitor to face the 'ether drift'. All of them failed. The facile explanation that the earth might drag the ether along with it only led to other difficulties with the observed aberration of starlight, and could not resolve the problem. 

Study Materials on Classical Electrodynamics

Introduction:

Mechanics tells us how a system will behave when subjected to a given force. There are four forces in nature known (presently) to us. If we arrange them in order of decreasing strength, they would be:

1. Strong nuclear force
2. Electromagnetic force
3. Weak nuclear force, and
4. Gravitational force

We have often thought about questions, like: Where is friction? Where is the "normal" force that keeps us from falling through the floor? Where are the chemical forces that bind molecules together? Where is the force of impact between two billiard balls? The answer is that all these forces are electromagnetic.