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The Maxwell's equations in vacuum, in absence of charges and currents are written and are shown to imply wave equation for the electric and magnetic fields. The plane wave solutions, the electromagnetic waves, are shown to travel with a velocity equal to \(1/\sqrt{\mu_0\epsilon_0}\). The numerical value of this expression equals the velocity of light. This leads to the identification of light as electromagnetic waves.

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The Poynting theorem gives an expression for energy density and rate of flow of energy across a surface. Using these expressions, the energy density and other quantities are computed for plane wave solutions.

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Two problems with,Ampere's law and charge conservation, Maxwell's equations for time varying field are discussed. Maxwell modified the fourth equation by adding a displacement current.

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In absence of any medium and in free space, \(\rho=0, \vec{j}=0\), it is proved that the electric and magnetic fields satisfy wave equation.

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Several concepts and results valid for static fields need revision when one is considering the situation of time varying fields. Some of these are discussed here

For a volume distribution of current an expression for magnetization density,{\it i.e.} the magnetic moment per unit volume, is obtained. An expression for the magnetic field at large distances, in terms of magnetization density,  is derived.

The Biot Savart law for current carrying wire is explained.

 In this section we compute the leading term in the magnetic field of a current loop at large distances and obtain an expression for the magnetic moment of the loop.

1. Reduction of Two Body Problem to One Body Problem
2. General Properties of Motion
3. Differential Equation of the orbit