Name: resultant force from tugboats
Uploaded: 2023-09-22T11:49:19.000Z
Duration: 1 min 23 s
Channel: JoVE

L’addition vectorielle de deux vecteurs de force ou plus peut être effectuée à l’aide de la loi du parallélogramme pour obtenir la force résultante.
Prenons l’exemple d’un navire tiré par deux petits remorqueurs. Les deux forces, F1 et F2, agissent simultanément sur le navire.
Pour déterminer la force nette à l’aide de la loi du parallélogramme, tracez des droites parallèles aux deux vecteurs de force de sorte qu’un parallélogramme soit formé.
Maintenant, la diagonale du parallélogramme représente la force nette FN sur le navire due aux deux remorqueurs. Il est exprimé comme la somme vectorielle des forces F1 et F2 .
Supposons maintenant qu’une troisième force d’un autre remorqueur agisse sur le navire.
Un autre parallélogramme est formé, en utilisant FN et la troisième force F3. La diagonale de ce nouveau parallélogramme donne la force résultante sur le navire due aux trois remorqueurs.
Ici, la force résultante sur le navire est exprimée comme la somme vectorielle des trois forces.

<ol>
	<li>Hibbeler, R.C. (2016). Génie mécanique \u2012 Statique et dynamique. Hoboken, New Jersey : Pearson Prentice Hall. pp 18 à 22</li>
	<li>Bière, F.P. ; Johnston, E.R. ; Mazurek, D.F ; Cromwell, P.J. et Self, B.P. (2019). Mécanique vectorielle pour les ingénieurs \u2012 Statique et dynamique. New York : McGraw-Hill. page 29</li>
</ol>

addition vectorielle des forces

Lorsqu'il s'agit de comprendre les effets de forces multiples qui agissent sur un objet, l'addition vectorielle est un concept crucial à saisir. Ce concept mathématique peut être utilisé pour calculer la force nette qui agit sur un objet lorsque deux forces ou plus sont impliquées. Pour comprendre le concept de l'addition vectorielle, prenons l'exemple d'un navire tiré par deux petits remorqueurs. Les deux forces, F1  et F2, agissent simultanément sur le navire dans des directions différentes. La loi du parallélogramme peut être utilisée pour calculer la force nette agissant sur le navire. La loi du parallélogramme est utile dans l'addition vectorielle car elle fournit une méthode géométrique pour additionner deux vecteurs. Elle stipule que lorsque les côtés adjacents d'un parallélogramme représentent deux vecteurs, la diagonale passant par leur intersection représente la somme vectorielle des deux vecteurs. Pour appliquer cette loi dans le contexte du navire tiré par deux remorqueurs, des lignes parallèles aux vecteurs de force sont tracées pour former un parallélogramme. Ensuite, une ligne diagonale passant par l'intersection des deux vecteurs est tracée. Cette diagonale représente la force résultante ou nette agissant sur le navire en raison des deux remorqueurs. Cette force nette est exprimée comme la somme vectorielle des deux forces. Cependant, si une troisième force F3 est introduite, un autre parallélogramme est tracé. Cette fois-ci, la force résultante précédente F1  + F2 est utilisée comme un côté du nouveau parallélogramme, avec la troisième force F3 comme l'autre côté. Une fois de plus, la diagonale de ce parallélogramme représente la force résultante ou nette agissant sur le navire en raison des trois remorqueurs. Cette force nette sur le navire est exprimée comme la somme vectorielle des trois forces, à savoir F1  + F2 + F3. L'addition vectorielle est un outil puissant pour comprendre les effets de forces multiples agissant sur un objet. Elle est cruciale dans divers domaines, notamment la physique, l'ingénierie et les mathématiques. En comprenant la loi du parallélogramme et le concept de l'addition vectorielle, il est possible de faire des calculs et des prédictions précises sur la force nette agissant sur un objet.

Addition vectorielle des forces

Pour comprendre les effets de plusieurs forces agissant sur un objet, l’addition de vecteurs est un concept crucial à saisir. Ce concept mathématique peut être ...

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Vector Addition of Forces

resultant force from tugboats

Resultant force can be found with vector addition when two or more forces act on the same object. This idea helps explain how multiple pulls combine to create one net force. It is a key tool for understanding motion in physics.

A clear example is a ship pulled by two small tugboats. The forces, F1 and F2, act at the same time but in different directions. The net force on the ship is the vector sum of those two forces.

The parallelogram law gives a geometric way to add vectors. In this method, the two force vectors form adjacent sides of a parallelogram. The diagonal through their intersection shows the resultant, or net force.

To use the law for the tugboat example, parallel lines are drawn to both force vectors to complete the parallelogram. Then a diagonal is drawn across the shape. That diagonal represents the net force acting on the ship from the two tugboats.

A third force, F3, can be added in the same way. A new parallelogram is drawn using the previous resultant, F1 + F2, as one side and F3 as the other. The diagonal of this second parallelogram gives the total resultant force, written as F1 + F2 + F3.

Vector addition is useful in physics, engineering, and mathematics. It helps scientists and engineers calculate and predict the net force on an object. The parallelogram law makes that prediction easier to picture and measure.

Resultant Force from Tugboats

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key terms and concepts

Learn how vector addition uses the parallelogram law to find the resultant force on a ship pulled by two or three tugboats in physics.

Resultant Force from Tugboats | JoVE K12

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Resultant Force from Tugboats

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