Name: resultant forces in force and couple systems
Uploaded: 2023-09-22T11:49:22.000Z
Duration: 1 min 18 s
Channel: JoVE

Le système avec une force résultante équivalente et un moment de couple résultant ayant des lignes d’action perpendiculaires peut être réduit à une force résultante unique équivalente agissant le long d’une nouvelle ligne d’action.
Un système de forces concurrentes a les lignes d’action de toutes les forces qui se coupent en un point commun, de sorte qu’aucun moment n’est produit en ce point et peut être représenté par une seule force résultante.
Dans un système de forces coplanaires, les lignes d’action de toutes les forces et la force résultante se trouvent dans le même plan. Ainsi, le moment de couple résultant est perpendiculaire à la force résultante.
Le moment résultant peut être remplacé en déplaçant la force résultante d’une distance perpendiculaire telle qu’elle produit le même moment.
De même, dans un système de forces parallèles, toutes les forces et la force résultante sont parallèles au même axe.
Et le moment de couple résultant est perpendiculaire à la force résultante.
Ainsi, le système peut être réduit à une force résultante unique équivalente agissant sur le point situé sur l’axe perpendiculaire.

<ol>
	<li>Hibbeler, R.C. (2016). Génie mécanique \u2012 Statique et dynamique. Hoboken, New Jersey : Pearson Prentice Hall. p. 177 à 179.</li>
</ol>

simplification d'un système de forces et de moments couple i

Simplification of a Force and Couple System I

Le concept de réduction d'un système de forces et de moments couple en un système équivalent est essentiel pour simplifier l'analyse des corps rigides. Cette réduction permet des calculs plus simples et une meilleure compréhension des effets externes produits par le système. En particulier, les systèmes ayant une force résultante équivalente et un moment couple résultant ayant des droites d'action perpendiculaires peuvent être encore réduits à une seule force résultante équivalente agissant le long d'une nouvelle droite d'action. Il existe trois types principaux de systèmes de forces pouvant être simplifiés de cette manière : simultanés, coplanaires et parallèles. Un système de forces simultanées est constitué de forces dont les droites d'action se croisent en un seul point. En raison de cette intersection, aucun moment n'est produit au point, et le système peut être représenté par une seule force résultante agissant au point d'intersection. Cette simplification réduit considérablement la complexité du système de forces, permettant une analyse plus simple. Dans un système de forces coplanaires, les droites d'action de toutes les forces et de la force résultante se trouvent dans le même plan. Le moment couple résultant dans ce système est perpendiculaire à la force résultante, ce qui permet une simplification supplémentaire. Déplacer la force résultante d'une distance perpendiculaire peut produire le même moment que le système original. Un système de forces parallèles est constitué de forces parallèles à un même axe, la force résultante étant également parallèle à cet axe. Dans ce cas, le moment couple résultant est perpendiculaire à la force résultante, ce qui permet une simplification. Le système peut être réduit à une seule force résultante équivalente agissant sur un point situé sur l'axe perpendiculaire. Dans chacun de ces systèmes de forces, le processus de réduction des forces et des moments couple en une seule force résultante équivalente simplifie l'analyse et la compréhension des effets externes sur un corps rigide. Cette réduction est bénéfique dans les applications d'ingénierie, où les systèmes de forces complexes doivent souvent être analysés à des fins de conception et de sécurité. En comprenant les principes sous-jacents des systèmes de forces simultanées, coplanaires et parallèles, les ingénieurs et autres professionnels peuvent analyser et concevoir de manière plus efficace des structures, des machines et d'autres systèmes soumis à diverses forces. La réduction des systèmes de forces complexes à une seule force résultante équivalente permet des calculs plus simples et des conceptions plus efficaces et pratiques.

Simplification d'un système de forces et de moments couple I

Le concept de réduction d’un système de forces et de moments de couple à un système équivalent est essentiel pour simplifier l’analyse des corps rigides. Ceci...

simplification-of-a-force-and-couple-system-i

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Mechanical Engineering

Génie mécanique

Unit 1

Unité 1

Force System Resultants

Résultantes des systèmes de forces

KEY TERMS AND CONCEPTS

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resultant forces in force and couple systems

Force and couple systems can be reduced to a simpler equivalent system. This makes rigid body analysis easier because the external effect of the forces is captured with fewer elements. When the resultant force and resultant couple moment have perpendicular lines of action, the system may be reduced further to a single resultant force along a new line of action.

Three common force systems can be simplified this way: concurrent, coplanar, and parallel. A concurrent force system has lines of action that meet at one point. Because the forces pass through the same point, no moment is produced there, and the system can be replaced by one resultant force acting at that intersection.

A coplanar force system has all force lines of action in the same plane. In this case, the resultant couple moment is perpendicular to the resultant force. That allows the force to be shifted by a perpendicular distance while keeping the same moment as the original system.

A parallel force system has forces that are parallel to the same axis. The resultant force is also parallel to that axis. Here, the resultant couple moment is perpendicular to the resultant force, so the system can be reduced to one equivalent force acting at a point on the perpendicular axis.

These reductions are useful in engineering because complex force systems often need to be checked for design and safety. By using concurrent, coplanar, and parallel force systems, engineers can analyze structures, machines, and other rigid bodies more efficiently. Turning several forces and couple moments into one resultant force also makes the calculations simpler and the design process more practical.

Resultant Forces in Force and Couple Systems

resultant-forces-in-force-and-couple-systems

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simplification of a force and couple system i

Force and couple systems can be reduced to a simpler equivalent system. This makes rigid body analysis easier because the external effect of the forces is captured with fewer elements. When the resultant force and resultant couple moment have perpendicular lines of action, the system may be reduced further to a single resultant force along a new line of action. Three common force systems can be simplified this way: concurrent, coplanar, and parallel. A concurrent force system has lines of...

simplification of a force and couple system: ii

simplification-of-a-force-and-couple-system-ii

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key terms and concepts

Learn how concurrent, coplanar, and parallel force systems can be reduced to one equivalent resultant force and couple moment for simpler rigid body analysis.

Resultant Forces in Force and Couple Systems | JoVE K12

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Resultant Forces in Force and Couple Systems

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