Kinetics and Kinematics are regarded as part of classical mechanics associated with the motion of objects or bodies in different spaces. The significant difference between Kinetics and Kinematics is that kinetics deals with the study of different forces that result in motion. As against, kinematics is associated with the study of the actual motion of objects or bodies without the consideration of the force that causes the motion.
Generally, people get confused between these two terms considering them as synonyms of each other. But from the above-given description, I hope you have got the basic idea regarding the difference between these two terms.
Content: Kinetics Vs Kinematics
Comparison Chart
| Basis for Comparison | Kinetics | Kinematics |
|---|---|---|
| Basic | It is the study of forces acting on a body resulting in motion. | It is the study of motion of the object or body irrespective of the force applied. |
| Branches associated | Physics, Chemistry, Biology, etc. | Physics, Mechanics, etc. |
| Determines | Quantities like forces, torque etc. | Quantities like position, acceleration, velocity etc. |
| Mass | Major considerable factor | Not considered |
| Applied Force | Explicit factor | Not an explicit factor |
| Nature | Focuses on cause | Not focuses on the cause but the result. |
| Fundamental origin | Branch of Physics | Branch of mathematics |
| Example | A child running in a ground. | A ball falling on the ground. |
| Application | In automobile designing. | In the study of movement of celestial bodies. |
Definition of Kinetics
Kinetics (sometimes known as Dynamics) is the branch of mechanics that deals with the analysis of how the applied force or torque affects the motion of the body having specific mass. More simply, it is regarded as the cause of the motion. We know that whenever a body or a system of bodies move then it is a result of some kind of force or torque associated with it.
Let us consider an example to have a better idea about the same.
Suppose we are having a rotating toy and on pressing a button it undergoes rotational motion. So, basically, here the applied force makes the body rotate about a fixed axis. Such a study of force comes under kinetics. Thus, kinetics deals with the cause due to which the motion is occurring and in the above-given example, the rotational torque causes motion.
Here we are not concerned about how the motion is taking place (like the direction, velocity, acceleration, etc.) This is defined as Kinetics in Physics.
Definition of Kinematics
The word “Kinema” signifies motion. Kinematics is the sub-classification of mechanics that is associated with the study of the analysis of the geometrically possible motion of an object or objects in space. However, the cause of this motion is not considered in kinematics. Thus, it is concerned with “The way motion is taking place(concerning parameters)” but not with the reason for the motion.
In simplest terms, kinematics describes the motion of a body or object in terms of position, velocity, acceleration. However, here force, torque, and mass of the body are not taken into consideration. More specifically, we can say that it is a description of the position of bodies in space, the rate with which the particles constituting the body are moving (i.e., velocity), the rate with which the velocity is getting changed (i.e., acceleration).
Key Differences Between Kinetics and Kinematics
- Kinetics is the branch of physics that studies the cause that results in motion thus majorly considers force or torque. While kinematics is concerned with the parameters like position, acceleration, speed, etc. of the body while in motion.
- The branch of science including physics, chemistry, and biology majorly uses the principle of kinetics like in chemistry it is associated with the rate of chemical reaction while in the field of biology it deals with the effect of enzymes on biochemical reaction. On the contrary, kinematics is the branch of physics and mechanics concerning the amount of change occurred rather than how the change occurred.
- Kinetics considers the mass of the body as it deals with force and we know F = ma, thus mass is a major considerable factor in the case of kinetics. However, the study of kinematics never considers the mass of the body.
- When we deal with kinetics then force plays a crucial role as the different forces acting on the body is studied in kinetics. As against, though the motion of the body is the result of some applied force still kinematics is not concerned with the applied force.
- Kinetics is mainly defined as the branch of physics as it is concerned with how the motion is occurring. While kinematics is somewhat regarded as the branch of mathematics as it deals with the geometry of motion that calculates a variation in different variables with different functions.
Conclusion
Thus, from this discussion, we can conclude that as kinetics deals with the cause of motion thus the determining factors here are force, gravity, friction, and torque. But as kinematics deals with the type of motion thus, resulting in the study of its position in space with speed and acceleration.