# Course Fundamentals of optics

About the light as a wave and a ray.
Level 2 (without higher mathematics)
Level 2 requires school mathematics. Suitable for pupils.
1. 1
Lesson

## What is the (Angular) Wavenumber?

Here you will learn how wavenumber is defined, how it can be calculated and illustrated, and how it is related to angular wavenumber.

Related formulas
Formula

Formula

Formula

## Relationship Between Wave Number and Angular Wave Number

Related Illustrations
2. 2
Lesson

## Interference and How The Path Difference Causes It

Learn how constructive and destructive interference results from the path difference and how to mathematically add two sine waves.

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Formula

Formula

## Condition for Constructive Interference (Path Difference, Wavelength)

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3. 3
Video

## Classical Double-Slit Experiment explained simply in 16 minutes!

Derivations & Experiments
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Formula

## Double slit experiment (wavelength, path difference, slit distance)

Related Illustrations
Related Questions
1. How do You Determine the Focal Length of a Lens?