Coralys Colón Morales: Daily Physics

From the moment we wake to the moment we go back to sleep, we are surrounded by physics. We find it in every noise, collision, conversation etc. It’s amazing how every detail in our lives has its way of working and its explanation in physics. As I read several articles, which explained the relationship between physics and our daily life, I found myself interested in understanding how everything works. There is one particular article that I enjoyed best: “This is a love song: the physics of music and the music of physics”. This article explains several things like the frequency and vibration of a moving swing, how to break a glass of wine using resonance, how standing waves work in musical instruments. 

When you push a swing at a faster or slower rate than the rate of vibration it already has (its natural frequency), nothing happens (there is not difference in the speed at which it moves); but if you push it with the same rate it has, then there will be a change and large oscillations will be created. So by altering the natural frequency of the swing, we create resonance. 

We have all seen videos or heard of a person breaking a glass of wine by singing with a high and strong voice and it’s hard for us to believe that it’s even possible to achieve since no matter how hard we try, we can’t do it. Well the author of this article explains the way it is done. It is simply physics. The sound of the voice is what breaks the glass, but it’s not the volume of the sound, it’s the matching of the sound of the voice with the natural frequency of the wine glass. So if the natural frequency is 791Hz, then the sound of the voice has to be 791Hz, not even 790 nor 792. 

A standing wave is one that is produced when the reflection of a wave runs into the next wave. Standing waves can be found in different musical instruments. This article gives the example of a guitar, which is a musical instrument with strings. The string has no vibration at its ends and has maximum vibration in the middle. So as the vibration moves, it creates a repetitive pattern and that is a frequency that depends on the wavelength. A short string has a short wavelength and a high frequency. A long string has a long wavelength and a low frequency. That’s how the guitar emits a sound, by playing a sequence of frequencies at a time. If it’s a sequence of single frequencies, then the music will be in its simplest form. If it’s a sequence of different sequences, the music is polytonic and it can be played in a harmonious way. 

Therefore, whether you go to the park, sing or listen to music, you will find physics in everything you see or do. The more concepts you know, the better you will understand the things that surround you and that should be our goal.