Types of motion

Motion:

Motion can be defined as a phenomenon where the position of an object is changed over a time. A frame of reference is attached to an observer, and the change in location of the body relative to that frame is measured as time passes. Displacement, distance, velocity, acceleration, speed, and time are all mathematical words used to describe motion. An object is said to be at rest or motionless or immobile or stationary, or to have a constant or time-invariant location with respect to its surroundings if it does not change relative to a particular frame of reference. Absolute motion cannot be defined since there is no absolute frame of reference. As a result, everything in the cosmos may be thought of as being in motion. As motion can be applied to various systems of physics such as radiation, space-time, etc. and to shapes, images and boundaries as well, the motion can be said to change positions and configurations in space continuously.

Types of Motion:

There are certain types of motion based upon state of motion, direction, etc. The types of motion are:

1.     Oscillatory motion
2.     Rotational motion
3.     Translational motion
4.     Uniform motion
5.     Non- uniform motion
6.     Periodic motion
7.     Circular motion
8.     Linear motion

Let us understand in brief about each motion:

1. Oscillatory motion:

A motion which keeps on repeating itself is known as oscillatory motion. It is assumed that oscillatory motion continues forever if there would be an absence of friction, but in a practical situation, it stops eventually by reaching equilibrium.

The best example of oscillatory motion can be a pendulum of a clock or the string of a musical instrument.

2. Rotational motion:

When an item travels along its axis, all of its pieces move for a different distance in a given amount of time, this is known as rotational motion. In this motion, the force which drives TM is counterbalanced by resisting force TL and by dynamic force J dw/dt or inertia.

This can be denoted as

TM – TL = J dw/dt

Where J is inertia and is expressed in kg*m2

Examples of Rotational motion can be, wheel rotating in a moving vehicle or Earth rotating at its own axis.

3. Translational motion:

Transitional motion occurs when all sections of an item move the same distance in the same amount of time. In translation motion, there are two segregations, Curvilinear Motion and Rectilinear Motion.

1. Curvilinear Motion: When an object is following a curved path while being in transactional motion, it is said to be in Curvilinear Motion.
2. Rectilinear Motion: When an object is following a straight-line path while being in transactional motion, it is said to be in Rectilinear Motion.

Example of translational motion can be a cyclist cycling straight on the path.

4. Uniform motion:

Uniform motion occurs when an item moves at a consistent speed in a certain direction at regular periods of time. For instance, while a train moves at a constant speed in a straight-line, it is said to be in Uniform motion. Here, the value of friction would be zero.

The equation of Uniform Motion can be derived as,

Let v= initial and final velocity; t=time; and s= displacement;

Therefore, s=vt

Now, suppose, final velocity as v and initial velocity as u; consider a as an acceleration throughout time t; s= displacement,

So,

v= u + at

s= ut + 1/2at2

v2 – u2 = 2as

Example of a train can be taken here. A train is said to be in a uniform motion when it is travelling in a straight path at a constant speed.

5. Non-uniform motion:

If an object is moving at a different velocity at a regular interval of time and is covering a different distance in interval of equal time, then it is called non-uniform motion. Here, the value of acceleration will be non-zero.

Example of non-uniform motion can be a biker running his bike on a path which is not straight.

Under Non-uniform motion, there are two types of motion, uniformly accelerated non-uniform motion and non-uniformly accelerated non-uniform motion.

1. Uniformly accelerated non-uniform motion: When objects travel at various speeds in a time span of similar length and the acceleration remains constant. This indicates that in a given time interval, an object’s velocity will vary at a constant rate.
2. non-uniformly accelerated non-uniform motion:

When objects travel at various speeds in a given time interval and their acceleration varies across that time interval. This signifies that an object’s velocity does not fluctuate at a steady pace.

6. Periodic motion:

Periodic motion is basically similar to oscillatory motion, which means that motion keeps repeating itself after equal time intervals.

7. Circular motion:

An object is said to be in circular motion when the object moves in a circular path constantly. Here, the object speed should be constant.

8. Linear motion:

A motion in a straight line, without any divergence is known as linear motion.

Conclusion:

Everything in the universe may be said to be in motion. When objects move at different speeds in a particular time interval and their acceleration changes with time. This indicates that the velocity of an item does not change at a constant rate. If an object does not change in relation to a certain frame of reference, it is said to be at rest or motionless.