This is the first of the two most important lectures. This lecture covers the Lorentz force, which describes how particles move in electromagnetic fields.

We see the problems in the non-relativistic version that led to Einstein re-formulating the notions of space, time and relativity.

We introduce the corrected version, written in terms of tensors, including the Faraday tensor.

The last section introduces us the subject matter of Maxwell's equations, which describe how fields are affected by charges and currents. In this lecture we cover covariant differentiation and basic wave equations.