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Video Level 3

Differential Equations explained simply in 47 minutes!

Differential equations

In this Lecture you will learn to classify and to solve arbitrary differential equations (ODE / PDE) in 42 minutes.

Content of the video
  1. [00:16] Why do I need differential equations?
  2. [00:47​] What is a differential equation?
  3. [03:41​] Different notations of a differential equation
  4. [05:19​] What should I do with a differential equation?
  5. [06:31​] How to identify a differential equation
  6. [07:28​] What are coupled differential equations?
  7. [08:53​] Classification: Which DEQ types are there?
  8. [16:05​] What are DEQ constraints?
  9. [18:24] Difference between boundary and initial conditions
  10. [20:55​] Solving method #1: Separation of variables
  11. [21:08​] Example: Radioactive Decay law
  12. [22:50​] Solving method #2: Variation of constants
  13. [25:59​] Example: RL Circuit
  14. [29:14​] Solving method #3: Exponential ansatz
  15. [34:50​] Example: Oscillating Spring
  16. [41:15​] Solving method #4: Product / Separation ansatz
Lesson Level 3

Differential equations (DEQ): Important basics + 4 solving methods

Differentialgleichungen - Klassifizierung

Here you will learn the basics of differential equations (DGL), what types there are (ordinary, partial, linear, homogeneous) and 4 solving methods (separation of variables, variation of constants, exponential and separation ansatz).

Video Level 2

Ohm's law explained simply in 13 minutes!

Ohm-law

Here you will learn how to recognize Ohm's Law in a U-I diagram and how to apply the associated URI formula. Three examples are covered.

Content of the video
  1. [00:00] Hello there!
  2. [00:44] The 1st ingredient: Voltage
  3. [01:30] The 2nd ingredient: Electrical conductor
  4. [01:57] The 3rd ingredient: Electric current
  5. [03:28] Data points and Ohm's law as a graph
  6. [05:58] Ohmic conductors
  7. [06:44] Slope of the graph
  8. [07:52] Ohm's law as a formula
  9. [10:10] Electrical resistance
  10. [10:16] Example #1: Resistance unknown
  11. [10:42] Example #2: Voltage unknown
  12. [11:10] Example #3: Current unknown
Lesson Level 2

Ohm's law: Formula, Graph and 3 Easy Examples

Ohmsches Gesetz - linearer Zusammenhang zwischen Strom und Spannung

Here you learn Ohm's law, how it is expressed as a formula and as a graph. We also look at three examples.

Video Level 1

Voltage explained simply in 10 minutes!

Voltage

Here you will learn what voltage is, how it is generated by charge separation, how a voltage source can be created, and what voltage has to do with current.

Content of the video
  1. [00:00​] Hello there!
  2. [00:48​] Positive and negative electric charge
  3. [02:00​] Charge separation generates voltage
  4. [03:46​] Voltage is energy per charge
  5. [06:21​] Voltage source and electric current
  6. [08:57] Is voltage dangerous?