Motion: Definition, Examples, and Types of Motion

Motion is an important concept in physics that helps us understand how objects move. From the moving car to the hands of a clock, motion is all around us and plays a vital role in daily life. 

In this article, we will understand the definition of motion, its types, and real-life examples for better clarity.

Table of Contents

• What is Motion?
• Understanding Rest and Motion
• Why is Motion Relative?
• Different Types of Motion

What is Motion?

Observe the things in your surroundings and make a list. Classify whether they are moving or stationary.

But how do you differentiate whether a body is at rest or in motion? To understand that, let's observe the following pictures.

So, motion is the change in position of an object with respect to time and its surroundings.

Understanding Rest and Motion

Body in Motion: When a body changes its position with time and with respect to its surroundings, the body is said to be in motion. 

For example, the car and the dog are moving, i.e. they are changing their position with respect to the surroundings. Thus, we will say that they are in motion.

Body is at Rest: When a body does not change its position with time and with respect to the surroundings, the body is said to be at rest. 

The book and the clock kept on the table are not changing their position with respect to the surroundings, thus they are at rest.

(Note: the clock is at rest, but the hands of a working clock are in motion.)

Why is Motion Relative?

Imagine that you are on a vacation and you go to see the Statue of Liberty. What do you observe? Is the Statue of Liberty in motion or at rest?

Now, imagine that at the same time there is an alien ship in space that who is observing the Statue of Liberty as well. What do you think they will see? Will they observe the statue in motion or at rest?

A body can be at rest for one observer and at the same time in motion for another observer, i.e. it depends on the position of the observer. Thus, motion is relative.

While travelling in a train, when it stops at a station, sometimes you feel that your train is moving. But later on, you realise that the other train is actually moving. Why do you experience this?

This happens due to relative motion. When the nearby train moves and no fixed reference point is visible, it creates an illusion that your train is moving, even though it is actually at rest.

Different Types of Motion

Motion in daily life can be classified into different types depending on how the body moves.

• Translatory Motion: Motion in which every particle of an object travels the same distance in equal time. Translatory motion is divided into two types, Rectilinear Motion and Curvilinear Motion. 
• Circular Motion: Movement of an object along a circular path. Circular motion is also divided into two parts, i.e, Rotational Motion and Revolutionary Motion 
• Oscillatory Motion: To-and-fro motion about a fixed point.
• Periodic: Repeats after equal time intervals.
• Non-Periodic: Repeats at unequal intervals.
• Multiple Motions: Objects can show more than one type of motion at once.

And so far, we’ve seen that motion is a fundamental concept in physics that helps us understand how objects move, change positions, and interact with their surroundings. From simple daily activities to complex planetary movements, motion is everywhere in our lives.