Resonance is an interesting phenomenon... but how does it work? In this video we'll look at 4 examples that help us clarify what resonance is and how we've come to use it for our own benefit.
0:00 - Intro, MUSIC!
1:42 - Example 1 - Playground Swing: What is Resonance?
2:46 - Example 2 - The Sarangi: Resonance in Music
7:46 - Example 3 - Tacoma Narrows Bridge: Resonance, or Aeroelastic Flutter?
8:47 - Example 4 - Resonance of Nanoparticles Using Lasers
In simple terms, a system undergoes "resonance" when an external driving force is applied at regular intervals, and at very specifically the "natural" or "resonant frequency" of the system. When we apply a repetitive (periodic) external force onto our system at exactly the right times, the system ends up oscillating, with higher and higher amplitude. So that's what resonance essentially means.
I didn't want to make another video simply explaining what resonance is - there are already lots of brilliant resources out there explaining the intricacies of this topic. Instead, I wanted to make a video showing you different examples that really helped me understand the pervasiveness of the phenomenon that is resonance, in our everyday lives. We have to think about it all the time, either to use its effects for our own benefit, or to protect against negative effects.
And the examples that really helped me understand resonance a bit better were the ones that were related to my own personal life. Firstly, pushing a friend on a swing in the playground, was an easy-to-visualise example that I latched onto quickly when I first learnt about resonance. Secondly, the Sarangi (an Indian bowed instrument) is something I've been listening to for a long time now, being a fan of Indian Classical Music. And eventually I realised that it harnesses the power of resonance in a very beautiful way! And lastly, my Masters research project was based on the resonance of gold nanoparticles when high-energy lasers were fired at them.
The example of the Tacoma Narrows Bridge collapsing is an interesting one - it is often taught when resonance is explained, but it's not technically an example of resonance. Resonance occurs when a driving force is exerted periodically and at regular intervals, whereas the bridge was gaining all its energy from a continuous, unidirectional flow of wind. Therefore, the bridge oscillated as a result of aeroelastic flutter, not resonance.
Btw, I have a second channel now where I post all of my music - check it out here: / @_parthmusic
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