Kinematics and Dynamics of Rigid Bodies in Plane Motion

In mechanics, a rigid body has a separate meaning apart from the stiff thing. Here, a rigid body stands for a collection of points in the object’s mass. A rigid body is also explained as a solid object having no deformation. In a solid object which is a rigid body, the mass is distributed uniformly. These form a crucial area of study in competitive exams like GATE. For that reason, the article has discussed what a rigid body is. It has also provided kinematics and dynamics. It provides a rigid body definition that will also explain motion in a plane. 

Rigid Body

A rigid body can have deformations in some cases but they are almost negligible. The distance between rigid body points does not change and stays constant. The distance does not change due to time nor due to forces externally acting on it. A true rigid body does not exist in the discussions of special relativity. Rigid bodies also depend on principles of kinematics and dynamics. A rigid body stands for a collection of points in the object’s mass. A rigid body is also explained as a solid object having no deformation. In a solid object which is a rigid body, the mass is distributed uniformly. In certain aspects of physics, a rigid body can exist when its motion is less than the lightspeed. An example of a rigid body is a molecule where it has many point masses. Certain things have to be remembered:

• The position of any rigid body is relative to the position of many particles within it
• Angular, as well as linear components, exist. 

Kinematics and Dynamics

Kinematics and dynamics are two elements that are related to the study of a rigid body. Kinematics and dynamics have unique positions to offer to a rigid body. Kinematics is a subtopic of physics. Kinematics and dynamics are a part of classical mechanical subjects. Kinematics involves the following properties: 

• It does not consider the types of forces existing and acting on a thing
• Kinematics is concerned with point motions
• Kinematics deals with the analysis of velocity
• It also deals with the acceleration of the body. 

Dynamics is a part of physics as well. It is a subdivision of mechanical engineering. It shows the movement of things relative to the factors that affect them. These physical elements that affect a thing are:

• Mass
• Energy
• Force
• Momentum

So here we see two parts of studying a rigid body. Kinematics and dynamics are separate branches of physics studying the motion of things and particles. Kinematics gives values of the change in the motion when dynamics provides the reason proving those changes. Kinematics and Dynamics are both crucial in studying robotics, mechanics, and engineering. 

Motion in a Plane

Motion in a plane studies motion in a plane where there are only two dimensions. It is related to kinematics and dynamics. Motion in a plane is charted graphically. Motion in a plane is relative to a rigid body. Analysing motion in double dimensions is done through points charted on a graph on both axes. Motion in a plane includes the study of motions like:

• Projectile 
• Circular

Conclusion

A rigid body stands for a collection of points in the object’s mass. A rigid body is also explained as a solid object having no deformation. In a solid object which is a rigid body, the mass is distributed uniformly. The distance between rigid body points does not change and stays constant. The distance does not change due to time nor due to forces externally acting on it.