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Electrodynamics

Learn about the electromagnetic properties of our universe, for example about electric charges, currents, electromagnetic fields and so on.
Video
Level 3 (with higher mathematics)

Dirac's Delta Function

In this video you will learn what the Dirac delta function is. We also derive its properties and make examples.

Content of the video
  1. What is the delta function good for?
  2. 02:09 Delta function graphically
  3. 02:21 Integral of the delta function at the origin
  4. 03:08 Shifted delta function
  5. 03:41 Integral of the shifted delta function
  6. 04:33 Delta function is symmetric (even)
  7. 05:44 Delta function with a factor
  8. 06:38 Examples
  9. 07:52 Three-dimensional delta function
Video
Level 4 (for physics pros)

Electromagnetic Wave Equation Simply Explained

In this physics video, we first derive the two wave equations for an electromagnetic wave (for the E and B field components) and look at their properties.

Content of the video
  1. 00:00 Maxwell's equations in vacuum
  2. 00:27 Derivation of the EM wave equation
  3. 02:13 Velocity of an electromagnetic wave
  4. 03:17 Structure of the electromagnetic wave equation
  5. 05:00 E- and B-field are perpendicular to wave vector
  6. 07:24 E- and B-field are perpendicular to each other
  7. 08:15 Summary
Video
Level 2 (without higher mathematics)

Lorentz force simply explained in 6 minutes!

In this video you will learn how to determine the direction of the Lorentz force using left/right hand rule and how this force is calculated and related to the centripetal force.

Content of the video
  1. 00:00 What is Lorentz force?
  2. 00:28 Moving charge perpendicular to the magnetic field
  3. 01:12 Determine Lorentz force direction
  4. 02:40 Lorentz force qvB-equation
  5. 04:12 Movement at an angle to the magnetic field
  6. 04:59 Lorentz and centripetal force
  7. 06:20 Determine velocity of the electron