Examples of rigid body in the following topics:

 We can describe the translational motion of a rigid body as if it is a point particle with the total mass located at the COMâ€”center of mass.
 We can describe the translational motion of a rigid body as if it is a point particle with the total mass located at the center of mass (COM).
 Derive the center of mass for the translational motion of a rigid body

 In contrast, a physical pendulum (sometimes called a compound pendulum) may be suspended by a rod that is not massless or, more generally, may be an arbitrarilyshaped, rigid body swinging by a pivot (see ).
 Gravity acts through the center of mass of the rigid body.
 In case we know the moment of inertia of the rigid body, we can evaluate the above expression of the period for the physical pendulum.
 The important thing to note about this relation is that the period is still independent of the mass of the rigid body.
 However, it is not independent of the mass distribution of the rigid body.

 We have referred to particle, object and body in the same way.
 We considered that actual three dimensional rigid bodies move such that all constituent particles had the same motion (i.e., same trajectory, velocity and acceleration).
 By doing this, we have essentially considered a rigid body as a point particle.
 This concept of COM, therefore, eliminate the complexities otherwise present in attempting to describe motions of rigid bodies.
 Support the presence of COM in three dimensional bodies in motion

 This definition can be extended to rigid bodies by defining the work of the torque and rotational kinetic energy.

 In the previous atom on "Center of Mass and Translational Motion," we learned why the concept of center of mass (COM) helps solving mechanics problems involving a rigid body.
 The experimental determination of the center of mass of a body uses gravity forces on the body and relies on the fact that in the parallel gravity field near the surface of Earth the center of mass is the same as the center of gravity.
 The center of mass of a body with an axis of symmetry and constant density must lie on this axis.
 In the same way, the center of mass of a spherically symmetric body of constant density is at the center of the sphere.
 In general, for any symmetry of a body, its center of mass will be a fixed point of that symmetry.

 Free body diagrams use geometry and vectors to visually represent the problem.
 In physics, most problems are solved much more easily when a free body diagram is used.
 First you want to model the body, in one of three ways:
 What to include: Since a free body diagram represents the body itself and the external forces on it.
 Explain the significance of building a free body diagram in physics

 In physics, a force is said to do work when it acts on a body so that there is a displacement of the point of application, however small, in the direction of the force.
 Also, from Newton's second law for rigid bodies, it can be shown that work on an object is equal to the change in kinetic energy of that object:

 Those two conditions hold regardless of whether the object we are talking about is a single point particle, a rigid body, or a collection of discrete particles.


 If two objects are connected by a perfectly rigid connector then they may be thought of as the same object.
 Perfectly rigid connectors cannot stretch nor deform, and transfer forces instantaneously from one side of the connection to the other.
 Thus it can be said that a perfectly rigid connection makes two objects into one large object.
 However, many materials are sufficiently rigid, so that using the perfectly rigid approximation is useful for simplicity's sake.
 Analyze the affect a rigid connection has on the movement of objects