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15.12:

Equation of Motion: General Plane motion

JoVE Core
Mechanical Engineering
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JoVE Core Mechanical Engineering
Equation of Motion: General Plane motion

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The motion of a rigid body in a general plane occurs due to externally applied forces and couple moments acting upon it. Newton's second law gives the translational motion of the center of mass of the body along each axis. Furthermore, the rotation of the body's center of mass caused by couple moments can be expressed as the product of the moment of inertia and the angular acceleration. These equations of motion can be generalized to any point on the body by expressing the moment equation as the sum of the moment about the center of mass and the moment due to translational motion about that specific point. For the object undergoing rolling without slipping, the moment equation for the point O is the sum of the moment due to the center of mass and the moment due to the translational motion of the center of mass. In this case, using a parallel axis theorem, the moment equation can be expressed in terms of the moment of inertia of the object at about point O.

15.12:

Equation of Motion: General Plane motion

In the context of a rigid body's movement within a general plane, it is important to understand that this motion is typically triggered by external forces or couple moments exerted onto it. This principle can be explained through Newton's second law, which stipulates the translational motion of the body's center of mass along each axis.

Moreover, the body's center of mass experiences a rotational effect as a result of these couple moments. This rotation can be articulated as the product of the angular acceleration and the moment of inertia. These equations of motion can be extended to any point on the body. This can be achieved by representing the moment equation as the sum of two components: the moment about the center of mass and the moment due to the translational motion about a specific point on the body.

For an object that rolls without slipping, there is a specific moment equation for the point in contact with the floor, point O. This equation is the summation of the moment due to the translational motion of the center of mass and the moment due to the center of mass itself. In such instances, the moment equation can be expressed using the parallel axis theorem. This theorem allows us to represent the moment equation in terms of the moment of inertia of the object at about point O. The exploration of these principles provides valuable insights into the intricate dynamics of a rigid body's motion within a general plane.