First Principles of Nature
Nature operates on a set of fundamental principles which cannot be explained in terms of anything simpler. Understanding natural phenomena in terms of these principles leaves no uncertainties behind. No additional explanations are possible and if we accept those principles as really fundamental, none are necessary.
To understand the current flow in conductors one has to accept the following three principles:
- an object in motion will maintain its velocity and direction until diverted by an external force (Principle of conservation of momentum),
- a stationary electric charge emits a radially symmetric force field which decays as the square of the distance from the charge (Principle of Coulomb force),
- electric field emitted by a charged particle is diverted from its radial direction by the motion of the charge in conformance with the classical mechanics. The absolute velocity of the emitted field, on the other hand, is unchanged regardless of the velocity of the emitter. (Principle of relativity).
We will devote considerable time to explaining the last two of the above principles as the need arises.