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Courses

A course is an ordered learning unit that will take you step by step through a comprehensive physics topic so that by the end you will have mastered it.

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Lesson

Density of states (1d, 2d, 3d) of a free electron gas

Here you will learn how to derive the 1d, 2d, and 3d density of states of a free electron gas from the k-volume and the dispersion relation.

Lesson

Electromagnetic wave and its E-field and B-field components

Here you will learnthe wave equations for the E-field and B-field of an electromagnetic wave and how it can be simplified to a plane wave.

Exercise with solution

Capacitor with and without dielectric in comparison

In this exercise with solution about the plate capacitor, the capacitance, voltage and energy must be compared with and without dielectric.

Exercise with solution

Charge in a thundercloud

The exercise teaches you how to calculate the charge of a thundercloud using the capacitance and E-field in the plate capacitor.

Exercise with solution

Create a plate capacitor with a certain capacitance

In this exercise (with solution) you have to calculate the distance between the capacitor plates for a given capacitance and and than use relative permittivity.