What is the difference between SHM,oscillation and vibratory motion?

[mremadahmed]

What is the difference between SHM ,oscillation and vibratory motion?

How many types of oscillations/vibratory motion are there?
If shm is one type of oscillation the what are the other types?

Can anyone please explain?

 

[Naty1]

Different people probably use the terms a bit differently...

Simple harmonic motion is typically considered to be a type of periodic motion...and it may decay or not as used in everyday language.

Oscillation is a more general term,...

oops: I just checked Wikipedia...and they refer to an oscillating weight on a spring and as
simple harmonic motion...and as 'oscillations' in another article...

Wiki says:

Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point.

I never heard of it used that way.

Aboard a boat, one refers to 'engine vibration' meaning the engine is missing, maybe a mount is loose, or maybe the drive train is out of alignment...as in a bent propeller.
I'd love to know where the 'equilibrium point' is in such a situation.

So Ill change my opening line to 'there is no consistency' ...

 

[Studiot]

OK.

Oscillation and vibration mean basically the same thing,

However

The term oscillation is usually reserved for periodic motion in which the whole body particpates as a rigid body, eg the oscillation of a mass on a spring or the oscillation of a pendulum. In essence the whole of the body is doing the same motion.

The term vibration usually refers to some kind of motion where one part of the body goes one way and another part goes another way. This usually means flexural vibration and larger objects such as buildings or bridges or electric cables. You can here cables vibrating in the wind where they are acting like guitar strings and different parts of the string are exefcuting different motions.

Simple harmonic motion means that there is no loss of energy to for instance friction so once set going the oscillation will never cease. It is characterised by a sinusoidal displacement graph.
Damped simple harmonic motion introduces some form of energy dissipation whilst maintaining the sinusoidal form.

You should also note that wave motion is different again.

Oscillations, vibrations and SHM refer to one one single vibrating or oscillating entity.

Wave motion occurs when there are many similar oscillators that have some form of coupling to transfer the motion or energy from one to the other.

 

[BruceW]

AFAIK vibration and oscillation are general terms to describe behaviour qualitatively. And SHM means something more specific (mathematically) $\ddot{x}=-kx$

 

[PJC01]

SHM (Simple Harmonic Motion) is a specific type of oscillation or vibratory motion in which the restoring force is directly proportional to the displacement from equilibrium and acts in the opposite direction. This results in a periodic motion that follows a sinusoidal pattern. Other types of oscillations or vibratory motions may have different restoring forces or patterns, such as damped oscillations or forced vibrations.

There are many types of oscillations and vibratory motions, as they can occur in various systems and under different conditions. Some common examples include pendulum motion, spring-mass systems, sound waves, and electromagnetic waves. Each type of oscillation or vibratory motion has its own unique characteristics and behaviors.

It is important to note that SHM is a specific type of oscillation, but not all oscillations are SHM. SHM is often used as a model for studying other types of oscillations, as it is a simple and well-understood example.

In summary, the difference between SHM, oscillation, and vibratory motion lies in the specific characteristics and behaviors of each type. While SHM is a specific type of oscillation, there are many other types that can occur in various systems and under different conditions.