The speed of a wave is calculated by multiplying the frequency of the wave by its wavelength. This is one of the key equation in physics (in the same category as f=ma or V=RI), and is applies to all types of waves. It is so important that it is called "The Wave Equation"!

In this video I will derive this equation for you so that you really understand where it comes from and its implications. And then, it will be time to play a little with it: We will measure the speed of light by using a microwave oven, a slice of cheese and the wave equation.

After describing a little the theory (the establishment of standing waves, why microwaves heat food etc…), I will carry out the measurement. You will see that we will find a value for the speed of light very close to the commonly accepted 3 x 10^8 m/s.

This video is also an occasion to show how to carry out a simple physics measurement, how to analyse the uncertainty on such measurement and how to propagate this uncertainty to the value which is being calculated (Here the speed of light).

**** Content of this video ****
0:00 The Wave Equation - Introduction
0:45 How does a particle move in a (transversal) wave?
2:11 The wave equation - Derivation with period
2:49 What is frequency ?
3:20 The wave equation - Derivation with frequency
4:10 How to measure the speed of light? (theory)
7:00 How to measure the speed of light? (measurement)
9:43 How to measure the speed of light? (data analysis)

**** Credits ****
Music by Edouard Reny.

**** More Info ****
This video is produced and presented by Edouard Reny, Ph.D. in solid state chemistry and private tutor in Physical Sciences.

For access to great resources that will help you with your studies of high school Physics, visit and subscribe to the "Physics Made Easy" website:
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Edouard provides one-on-one private tuition in Physics (face to face or by Skype). If you wish to contact him, visit his website: [ Ссылка ]

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