Name: couple moment work in rotation
Uploaded: 2023-09-22T11:49:20.000Z
Duration: 1 min 12 s
Channel: JoVE

Considere un cuerpo rígido con dos fuerzas iguales y opuestas que actúan en dos puntos separados por una distancia.
Esta pareja produce un momento igual a la fuerza multiplicada por la distancia entre ellos. Como resultado, el cuerpo rígido se somete a traslación y rotación para alcanzar la posición final.
Durante la traslación, el trabajo de una fuerza es igual y opuesto al trabajo de otra fuerza. Por lo tanto, el trabajo neto realizado por las dos fuerzas durante la traslación es cero.
Sin embargo, durante la rotación, el desplazamiento angular debido a una de las fuerzas da un desplazamiento lineal equivalente que resulta en trabajo.
Expresando el trabajo en términos de desplazamiento angular y usando la expresión para la magnitud del momento de la pareja se da la cantidad final de trabajo realizado, que depende del momento de la pareja y del ángulo de rotación.
Si el momento de la pareja y el ángulo de rotación tienen el mismo sentido, el trabajo realizado por el momento de la pareja es positivo.
En cambio, si tienen el sentido contrario, el trabajo realizado es negativo.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica: Estática. Decimocuarta edición, Nueva Jersey: Pearson. Sección 11.1, pág. 582.</li>
	<li>Meriam, J.L., Kraige, L.G. y Bolton, J.N. (2016). Ingeniería Mecánica: Estática y Dinámica. Octava edición, Singapur: John Wiley & Sons. Págs. 393-394.</li>
	<li>Beer, F.P., Johnston, E.R., Mazurek, D.F., Cornwell, P.J. y Self, B.P. (2016). Mecánica vectorial para ingenieros. Undécima Edición, Nueva York: McGraw-Hill Education. Sección 10.1A, págs. 577</li>
</ol>

trabajo de un momento de par

Work of a Couple Moment

La ingeniería mecánica implica el estudio del movimiento, la energía y la fuerza, y se ocupa del diseño, fabricación y mantenimiento de sistemas mecánicos. Un concepto importante en este campo es el momento de par, producido por dos fuerzas iguales y opuestas que actúan en dos puntos de un cuerpo rígido separados por una cierta distancia. Cuando el cuerpo rígido sufre un desplazamiento diferencial debido a un par, su movimiento puede dividirse en dos partes: la traslación igual de los dos puntos a sus posiciones finales y la rotación alrededor de uno de ellos. Durante la traslación, las dos fuerzas experimentan la misma cantidad de desplazamiento, pero en direcciones opuestas. Por lo tanto, el trabajo realizado por las fuerzas, siendo opuesto en signo pero igual en magnitud, da como resultado un trabajo nulo. Sin embargo, durante la rotación, la fuerza causa un desplazamiento angular, lo que conlleva un trabajo distinto de cero. El trabajo realizado durante la rotación se puede calcular como el producto de la magnitud del momento del par y el ángulo de rotación. Sí el momento del par y el ángulo de rotación tienen el mismo sentido, el trabajo realizado por el momento del par es positivo. Por el contrario, sí el momento del par y el ángulo de rotación tienen sentidos opuestos, el trabajo realizado será negativo. El trabajo realizado por un momento del par es un factor esencial a tener en cuenta en el diseño de sistemas mecánicos. Los ingenieros tienen en cuenta la cantidad de trabajo que se realizará durante la rotación, así como la magnitud y dirección del momento de par, para asegurarse de que el sistema funcione correctamente.

Trabajo de un Momento de Par

La ingeniería mecánica implica el estudio del movimiento, la energía y la fuerza, y se ocupa del diseño, la fabricación y el mantenimiento de ...

Education

Educación

JoVE Core

Mechanical Engineering

Ingeniería Mecánica

Unit 1

Unidad 1

Virtual Work

Trabajo virtual

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

couple moment work in rotation

Mechanical engineering studies motion, energy, and force, and it uses the idea of a couple moment to describe how two equal and opposite forces act on a rigid body. A couple moment is created when those forces act at two points on the body that are separated by a distance.

When a rigid body moves because of a couple, its displacement can be split into two parts. First, the two points move by the same amount to their final positions. Then the body rotates about one of those points.

During the translation part, each force moves the same distance but in the opposite direction. Because the forces are equal in magnitude and opposite in sign, the work done in this step is zero.

The rotation part is different. Here, the force produces an angular displacement, so the work is not zero. The work done by the couple moment equals the magnitude of the couple moment times the angle of rotation.

The sign of the work depends on direction. If the couple moment and the rotation angle have the same sense, the work is positive. If they have opposite senses, the work is negative. Engineers use this idea when they design mechanical systems, since the amount of work during rotation matters, along with the size and direction of the couple moment.

Couple Moment Work in Rotation

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Work connects force, motion, and energy in mechanics. It happens when a force acts on an object and the object moves along the line of action of that force. Work can also be described as energy transfer caused by applying a force, which leads to a change in the object’s motion or position. Work is calculated as the force multiplied by the part of the displacement in the same direction as the force. It can also be written as the dot product of the applied force and the object’s displacement. In...

work of a couple moment

Mechanical engineering studies motion, energy, and force, and it uses the idea of a couple moment to describe how two equal and opposite forces act on a rigid body. A couple moment is created when those forces act at two points on the body that are separated by a distance. When a rigid body moves because of a couple, its displacement can be split into two parts. First, the two points move by the same amount to their final positions. Then the body rotates about one of those points. During the...

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Virtual work is a mechanics principle used to check equilibrium with imaginary motion. If a body is in static or dynamic equilibrium, the total virtual work from external forces and couple moments must be zero for any virtual displacement. A virtual displacement is an imagined small movement. It can be a shift or a rotation. The virtual work done by a force equals the force dotted with the virtual displacement in the force’s direction. For a couple moment, virtual rotational work is found by...

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Types of equilibrium in mechanical systems are stable, neutral, and unstable. These three cases help explain how a structure or object responds when it is pushed slightly away from balance. They are important for predicting whether a system will return to its original position, stay where it is, or move farther away. Stable equilibrium occurs when a system returns toward its original position after a small displacement. In this case, the potential energy is at a minimum. A cantilever beam...

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key terms and concepts

Learn how a couple moment does zero work during translation but non-zero work during rotation, and how sign depends on the direction of rotation.

Couple Moment Work in Rotation | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

mechanical engineering

Couple Moment Work in Rotation

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