## Euler-Lagrange Equation in 13 Steps

Here you learn the derivation of the Euler-Lagrange equation, which a function q(t) must satisfy for a functional S[q] to become stationary.

Here you will learn the laws of **motion of bodies** (e.g. particles, cars, planets) under the influence of **mechanical forces**. Master the power to predict the future location and state of these bodies - whether the body is particle-like or wave-like.

Here you learn the derivation of the Euler-Lagrange equation, which a function q(t) must satisfy for a functional S[q] to become stationary.

Here, mechanical pressure is defined as a physical quantity and explained simply using examples.

Here it is explained quite simply what the mechanical momentum is, how you can calculate and illustrate it.

Here you will learn all about Minkowski diagrams, which are used to visualize special relativity (e.g. length contraction, time dilation).