Vibration - Eternal motion
Everything in life is vibration
- Albert Einstain
Our human senses are not powerful as we think. We miss many events that happen in nature. Even though we have the most evolved conscious but our sensory perception is not on par with other living organisms.
The sense of vibration can be seen from different viewpoints. It can be viewed as a physical event and modeled it using the laws of physics and mathematics, It can be viewed as a philosophical thought of the cycle of life and even it can be viewed in spirituality as a connection to the unknown creator.
The essence of vibration can be best understood using the modern scientific formulation. This article will be a bird's eye view of vibration in our life and I will explain why I call vibration the "eternal motion".
This article will give a scientific explanation. This explanation may not be scientifically accurate but will provide a good intuition of the concept.
TO AND FRO MOTION
To and fro, back and forth or here and there all these verbal expressions mean the same thing. In a very general view, this expression indicates the movement of someone or something forward or backward followed by a return to the same position. This in general indicates many ideas such as emotional state, relationship, or a physical thing. We are only interested in the physical aspect of to and fro motion.
As a human, we all would have seen the flapping of wings by a bird while flying this is a classical example of to and fro motion. This type of motion can be best understood by observing the wings of a bird or an insect. Now if you see the following picture you may get a visual idea of this here and there motion, or back and forth motion.
REPETITIVE PERIODIC MOTION
Repeat - An action that is performed more than once (like breathing).
Periodic - An event occurring at intervals of time (like the beating of the heart).
Motion - Some movement through time which is defined using Newton's second law.
Once we have an idea about to and fro motion the next step is to understand the essence of "repetitive periodic motion". As each word is defined it will be clear for you. A repetitive periodic motion is a motion that occurs more than one time in specific intervals of time. The best example of this is our heart. The heart has some movement as a whole so it is exhibiting repetitive periodic motion. I.e. in general a human heartbeat 60 to 100 times in a minute (This is given in a range because the heartbeat depends on many factors) and this process can be modeled using Newton's laws of motion.
Now we are clear about to and fro motion, time interval, and repetitive periodic motion (If you are not able to understand this contact me through the link provided at the end or ask your doubt in the comment).
OSCILLATION AND VIBRATION - A scientific approach to understanding repetitive periodic to and fro motion
When even we describe a thing we describe it through a physical quantity or a property, for example, we describe the movement of a car using speed or velocity, and we describe the dimensions of an object using size. In a similar way, repetitive periodic to and fro motion can be described using frequency.
FREQUENCY - Frequency is the number of occurrences of a repeating event per unit of time. For example, a high E string in a guitar goes up and down from the rest position 330 times in a second therefore the frequency of vibration of the high E guitar string is 330 Hz. Normally 1 Hz is the occurrence of one event in one second.
So, frequency is an important property to understand vibration. There are many consequences of frequency in a physical understanding like wavelength and wave period. wave number etc. When we deal with a repetitive periodic motion we always express the motion in terms of waves.
WAVES - Waves are the disturbance caused by repetitive periodic motion. The disturbance travel in a medium usually air, water, metal, etc. Even our human ear is working due to the disturbance caused by various events. Broadly speaking waves are the physical and mathematical consequence of vibrations and oscillations. If you see the previous image representing the flapping of wings of a bird, the bottom of the image is a curved line. This is not a random curve, mathematically it is a sine wave that is obtained from the rotating vectors. So a flapping of a bird's wing along with time represents a wave. At first, I actually felt the hoe an up-down motion (almost straight) can form a curve but it can. Try it your self take a long piece of paper and move the paper in a direction with constant velocity, on the other hand, use a pen and move your hands up and down you can see a similar pattern of flapping of a bird's wing. Physically it forms a sine curve but mathematically we can obtain many things from it like the frequency or the system which is causing it, wavelength, wavenumber, etc (this will be dealt with in detail in another blog).
The idea that we should understand here is that whenever there is a vibration, as a consequence of that vibration waves are formed and the nature of vibration can be understood by studying the waves.
OSCILLATIONS - "Oscillation is the repetitive or periodic variation, typically in time, of some measure about a central value often a point of equilibrium or between two or more different states". If someone search in Wikipedia this is the answer they get. Getting answers is not important but understanding them is important.
Now if you take the flapping of wings the wings go up as much as they can and the wings move down as much as they can so, they are moving between two different states keeping the 2nd and 4th stage as equilibrium position so the wings of a bird are oscillating around a mean point.
There is another example of oscillation in a non-physical way a child's mind oscillates between choosing a chocolate and ice cream. So anything that changes its state between two states can be considered oscillations.
The following show a spring and mass system (an ideal system in physics to study different phenomenon). when the spring is at rest the mass and spring remain in their stable state. when it is stretched or oppressed from the stable position it starts to oscillate between a compressed state and stretched state (You may have a question that why this happens? for now it is not our interest it will be dealt with afterward). Thus the mass and spring oscillate from their stable position. Along with it a graphical representation of the position of the mass over time is plotted, which forms a sine curve it represents a simple form of mechanical wave.
So oscillations are also to and fro motion. Oscillations describe the to and fro motion of almost everything from mechanical systems, dynamical systems, and biological systems to mind and emotions. The oscillations can be best described using frequency and a waveform. The frequency gives the energy of the oscillation, the quality of vibration, and more similarly the waveform give the details about the origin, state, and future of the oscillations. Oscillations occur from the very atomic level to a very large level like in space-time or even a galaxy can oscillate. Almost all living and non-living bodies exhibit oscillatory motion or oscillations.
Oscillations can be of a periodic nature, non-periodic nature can be linear, or cyclic it can be anything. The mathematics of oscillation deals with the quantification of the amount that a sequence or function tends to move between extremes. In modern physics, we use oscillations to find the state of the particle. So the direct consequence of oscillations is waves.
VIBRATION - Vibration literally means shaking, which is a Latin word. So shaking in one dimension is a to and fro motion and vibration in three dimensions is here and there motion. Mostly vibrations take place as a mechanical phenomenon. A mechanical phenomenon is a physical phenomenon associated with the equilibrium or motion of objects. A physical phenomenon is a natural phenomenon involving matter and energy.
Some of the best examples of vibration are sound from our vocal cord, from musical instruments, the membrane of loudspeakers, vibrations of water molecules while heating, the vibration of mobile phones, and more. So vibration is also a to and fro motion that exhibits a mechanical phenomenon.
THE CONFUSION - Are Oscillation and vibration the same or different
This confusion actually occurs for all the students but I have a good explanation to face this trick question. First, let us summarize what we know.
- Both oscillations and vibrations are to and fro motion.
- Both oscillations and vibration can be represented as waves and their direct consequence is the formation of waves.
- Both oscillation and vibrations fundamentally represent the same thing.
Now look at the question from a deeper point of view we can have a clear question "If oscillations and vibrations are the same phenomenon which is to and fro motion the why some to and fro motion is called vibrations and few to and fro motions are called as oscillations?"
It should not be surprising for you that there is no perfect answer for this but there is a convincing justification for this which is discussed below.
Well these two words mean the same phenomenon but we use them in a different context.
Scientifically speaking oscillations can mean any event that has the essence of to and fro motion. Like the movement of tires on gravel, any random to and fro motion, the to and fro motion of magnetic and electric field which forms a light, the to and fro motion of a pendulum, the motion of a swing, the motion of a sew-saw and more. Oscillations are mostly desirable which means it is done wanted like if you want to swing a swing you have to do it and it can be changed accordingly. What I mean to say is that if you want to move a swig for a certain distance you can move it according to your desire.
Oscillations mostly occur as a whole. Consider the swing, the swing is made up of many atoms or it is made of many individual particles while oscillating the individual particles act as one single particle and exhibit an oscillation.
If you take vibration, it seems more random than oscillation but it is not. the vibration is mostly undesirable which means we don.t obtain what we want. For example, take a tuning fork if you hit a tuning fork it will have a to and fro motion. Now if you take a tuning fork that produces an A note on hitting it you can only get a A frequency you can't get a C frequency from it without modifying the tuning fork. Similarly in all mechanical systems like cars, the bike we don't expect vibration to take place but it happens whit a certain frequency call as natural frequency. So vibration can't be decided for the mechanical system, the system will vibrate on its own.
Vibrations mostly occur as individual particles. So if you take vibrations all the particles vibrate in a very random fashion and provide a net vibration as a whole. If you take the tunning fork it gives an A frequency but it is provided by superimposing many rand vibrations in the material of the tuning fork.
Another important aspect is that vibration is mostly associated with the loss of energy but in oscillations, we provide energy to perform it. This can be best understood by taking a drummer as an example. A drummer swings his hand and hits the stretched membrane of the drum, here the action of hitting the drum i.e the motion of the hand can be considered as an oscillation whereas the to and fro motion of the drum membrane is vibration.
So vibration and oscillation on a very basic level are the same which represent the to and fro motion but in a scientific viewpoint, they are different and use to denote the to and fro motion in different conditions.
VIBRATION - Eternal motion
Eternal means existing or lasting forever. Each object that is visible to our eyes is made up of atoms and molecules. Mostly these particles have their own world to exist following some interesting rules. Now when you put a pollen grain on the surface and observe the interface through a microscope it will be seen that this pollen grain will jump here and there we don,t know why this happens in a macroscopic view. When we see it at a microscopic level it is clearly seen that it is because of the collisions of the washer molecules and the pollen grains, so for a collision to happen we require energy. The energy in a mass is stored via the mechanical phenomenon of vibration. So, everything in this world vibrates on its own and the reason for that is unknown. Even when the temperature is 0K (the coldest known temperature) the molecule has a vibration. So this undesired to and fro motion is kind of making the world stable by vibrating. That is why I call vibration eternal motion which is everlasting.
When anything vibrates it produces waves (a disturbance in space), so each and every object including us is emitting certain vibrations and these play an important role. The consequence of this is resonance, natural frequency, constructive waves, destructive waves, and more (These will be dealt with in a different blog). So vibrations connect us to the cosmos.
VIBRATION OF A GUITAR STRING
https://gfycat.com/warpedexcellenthairstreakbutterfly
DO VISIT THE ARCHIVE TO EXPLORE MORE
Hope this article was useful and I hope you learned something from it.
