# Course: Fundamentals of Optics

About the light as a wave and a ray. 1. 1

## How do You Determine the Focal Length of a Lens?

Here you will learn how to measure/determine the focal length of a lens using the lens equation.

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2. 2

## What is the Optical Power of a Lens?

Here you will learn what optical power is and how it is related to the focal length. You will also learn what diopters are.

3. 3

## What is Wavelength?

What is the wavelength defined and what unit does it have? How can I determine it?

4. 4

## What is the Phase Velocity of a Wave?

Here you can find out what the phase velocity of a wave is and how you can calculate it using a formula.

5. 5

## 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.

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6. 6

## What is the Refractive Index?

Here you will learn the definition of the refractive index and how it relates to the speed of light and the wavelength of light.

7. 7

## 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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8. 8

## Double-Slit Experiment with Light

Young's double-slit experiment with light. You learn how the interference pattern of the double-slit is formed and which role light diffraction plays.

Exercises with solutions Wavelength of The Monochromatic Light in a Double-Slit Experiment
Derivations & Experiments

## Double-Slit Formula

Here we derive the double-slit formula, which you can use, for example, to find the wavelength of light using a double-slit experiment.

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