Derivation of Kinematic Formulas

Here is the derivation of the four-kinematics formula mentioned above:

Derivation of First Kinematic Formula

We have,

Acceleration = Velocity / Time

a = Δv / Δt

We can now use the definition of velocity change v-v0 to replace Δv.

a = (v-v0)/ Δt

v = v0 + aΔt

This becomes the first kinematic formula if we agree to just use t for Δt.

v = vo + at

Derivation of Second Kinematic Formula

Displacement Δx can be found under any velocity graph. The object’s displacement Δx will be represented by the region beneath this velocity graph.

Δx is a total area, This region can be divided into a blue rectangle and a red triangle for ease of use.

The blue rectangle’s area is v0t since its height is v0 and its width is t. And The red triangle area is [Tex]\frac{1}{2}t(v-v_{0})     [/Tex] since its base is t and its height is v-v0.

The sum of the areas of the blue rectangle and the red triangle will be the entire area,

[Tex]\Delta{x}=v_{0}t+\frac{1}{2}t(v-v_{0})[/Tex]

[Tex]\Delta{x}=v_{0}t+\frac{1}{2}vt-\frac{1}{2}v_{0}t[/Tex]

[Tex]\Delta{x}=\frac{1}{2}vt+\frac{1}{2}v_{0}t[/Tex]

Finally, to obtain the second kinematic formula,

[Tex]\Delta{x}=(\frac{v+v_{0}}{2})t[/Tex]

Derivation of Third Kinematic Formula

From Second Kinematic Formula,

Δx/t = (v+v0)/2

put v = v0 + at we get,

Δx/t = (v0+at+v0)/2

Δx/t = v0 + at/2

Finally, to obtain the third kinematic formula,

[Tex]\Delta{x}=v_{0}t+\frac{1}{2}at^{2}[/Tex]

Derivation of Fourth Kinematic Formula

From Second Kinematic Formula,

Δx = ((v+v0)/2)t

v=v0+at  …(From First Kinematic Formula)

t = (v-v0)/a

Put the value of t in Second Kinematic Formula,

Δx = ((v+v0)/2) × ((v-v0)/a)

Δx = (v2+v02)/2a

We get Fourth Kinematic Formula by solving v2,

[Tex]v^{2}=v_{0}^{2}+2a\Delta{x}[/Tex]

Kinematics | Definition, Formula, Derivation, Problems

Kinematics is the study of motion of points, objects, and systems by examining their motion from a geometric perspective, without focusing on the forces that cause such movements or the physical characteristics of the objects involved. This study area uses algebra to create mathematical models that describe these motions, essentially treating it as the mathematics behind how things move.

Kinematics is a field of classical mechanics that deals with the motion of points, objects, and systems of objects. Kinematics is sometimes referred to as “motion geometry” by some professionals. Let’s have a look at the formula for kinematics.

In this article, we shall learn about kinematics, which is the study of motion, along with its formulas, derivation of kinematics formula, examples and others in detail.

Table of Content

  • What is Kinematics?
    • Kinematics Definition
  • Kinematic Formulas
  • Derivation of Kinematic Formulas
    • Derivation of First Kinematic Formula
    • Derivation of Second Kinematic Formula
    • Derivation of Third Kinematic Formula
    • Derivation of Fourth Kinematic Formula
  • Kinematics Solved Examples
  • Practice Problems on Kinematics

Similar Reads

What is Kinematics?

Kinematics is concerned with the trajectories of points, lines, and other geometric objects to describe motion. Furthermore, it concentrates on deferential qualities such as velocity and acceleration. Astrophysics, mechanical engineering, robotics, and biomechanics all use kinematics extensively....

Kinematic Formulas

The kinematics formulas deal with displacement, velocity, time, and acceleration. In addition, the following are the four kinematic formulas:...

Derivation of Kinematic Formulas

Here is the derivation of the four-kinematics formula mentioned above:...

Key Concept in Kinematics

Kinematics is a branch of mechanics that describes the motion of objects without considering the causes of this motion (i.e., forces). It involves the study of displacement, velocity, and acceleration of moving objects....

Position and Displacement

Position is a vector quantity that represents the location of an object in a given frame of reference. It is often described using coordinates in one, two, or three-dimensional space....

Speed and Velocity

Speed is a scalar quantity that measures the rate at which an object covers distance. It only has magnitude and no direction. Speed is always positive or zero....

Acceleration

Acceleration is the rate at which an object’s velocity changes with time. It indicates whether an object is speeding up, slowing down, or changing direction....

Kinematic Equations for Rotational Motion

Equation of motion for rotational motion are:...

Motion Graph

Various motion graphs are added below:...

Kinematics Question and Answer

Question 1: In kinematics, what are the various variables?...

Kinematics Solved Examples

Example 1: For the time span t = 7s, an automobile with a beginning velocity of zero accelerates uniformly at 16 m/s2. Do you know how far it’s travelled?...

Practice Questions on Kinematics

Q1. A car travels at a constant speed of 60 km/h for 2 hours. How far does the car travel in this time?...

Kinematics – FAQs

What is kinematics in physics?...