Translational Motion – equations, definition, types, examples

A particle is said to be in motion if it changes its position with time. The particle may go straight, may move in a circular path, may spin around an axis, or may roll on the floor. Considering these different ways of changing its position, Scientists have said that a particle can have three types of motion – Translational motion, Rotational motion and Mix motion. In this article, we are going to explain the Translational motion of a particle, examples and equation of motion. All discussions will be based on Classical mechanics or Newtonian mechanics.

Contents in this article:

• Definition of Translatory Motion in Physics
• Examples of Translatory Motion
• Types of Translatory Motion
• Translational Motion Formula

What is Translational Motion in Physics?

You may know that a body consists of a large number of point-like particles. These are often called point masses. When a body moves, these points also move. If all points of the body move parallelly during its motion, then the motion will be called a Translational or Translatory motion. In this type of motion, all points of the moving body feel like they are at rest with respect to each other.

In the above image, one can see that when a spherical ball is sliding on the floor, any two points are also moving parallelly. So, the ball is in a translatory motion.

Is Translational Motion a rectilinear motion?

In rectilinear motion or linear motion, the body moves in a straight line. That means all particles of the body also move in a straight line parallelly. So, the rectilinear motion is a Translatory motion. But, the Translatory motion can also occur in a curved path provided that every point moves in a parallel direction to each other at the same time. So, the curvilinear motion is also a type of translational motion.

Thus, all rectilinear motions are translational, but all translational motions are not rectilinear.

Types of Translatory Motion

There are two types of Translational motion. These are –

• Rectilinear Motion or Linear motion
• Curvilinear motion

In both types of motion, all points of a body move parallelly for the entire duration of its motion.

Examples of Translational Motion

Here are the 10 examples of Translational motion in our daily life –

1. The ideal walking of a man is an example of Translatory motion. During walking, all parts of the body move in the same direction parallelly.
2. Motion of a car in a straight line or in a curved path.
3. The motion of a body falling freely under gravity.
4. Motion of a Projectile.
5. Sliding of a body on the floor.
6. Sliding of an object in an inclined plane.
7. Motion of a bullet fired from a gun.
8. Cycling or riding a bike.
9. Swimming of fish in water bodies.
10. Motion of a boat on river or sea.

These are the best examples of translatory motion of a body.

Translational Motion Equations

All equations of Linear motion, Projectile motion, etc. are the equations of translational motion. Just ignore the equations for circular motion and rotational motion which are not the parts of translatory motion. Some common equations for translatory motion are as followings –

1. Displacement (x) of a particle moving with constant velocity (v), after a time t is, \color{Blue}x= vt
2. Velocity after time t of a particle moving with a constant acceleration (a) is, \color{Blue}v = (u + at)
3. Displacement after a time t of a particle moving with a constant acceleration (a) is, \color{Blue}s = (ut + \frac{1}{2}at^{2})
4. Kinetic energy of a body of mass m and velocity v is, \color{Blue}E_{k} =\frac{1}{2}mv^{2}.
5. See the equations of Projectile motion here.

There are so many formulae for translatory motion of an object, in different cases. Here, I have mentioned a few of those.

Summary

• An object can have three types of motion – translatory, rotational or spinning and mix motion.
• In Translatory motion, all points of the moving body move parallelly during its entire motion.
• There are two types of translational motion – Rectilinear motion and Curvilinear motion.
• All the equations except for the rotational and spinning motion are the equations of translatory motion.

This is all from this article on the Translational motion of a particle. If you have any doubt on this topic you can ask me in the comment section.

Thank you!

Related posts:

1. Kinetic energy in rotational motion
2. Projectile Motion equations