Name: tension in ropes and strings
Uploaded: 2025-05-22T09:06:17.000Z
Duration: 1 min 10 s
Channel: JoVE

La tension est décrite comme la force associée à une ficelle, une corde ou un câble étroitement tiré. Il s’agit d’une force de traction, car elle ne peut tirer qu’un objet et ne peut pas en pousser un.
Lorsqu’une corde est tendue, la force de tension est transférée à travers la corde à l’objet attaché. Ici, la force de tension équilibre le poids de l’objet.
Considérons une boîte de masse 'm' tirée par une corde à un angle thêta sur une surface lisse avec une accélération 'a'.
Dans cette situation, les forces sur la boîte sont l’attraction gravitationnelle agissant vers le bas, la force normale agissant vers le haut et la force de tension le long de la corde tirée.
La composante x de la tension est la seule force agissant dans le sens horizontal.
Dans le sens vertical, la composante y de la tension agit vers le haut avec la force normale, et l’attraction gravitationnelle agit vers le bas.
En appliquant la deuxième loi de Newton au système, on obtient la force de tension exercée par la corde et la force normale exercée par la surface sur la boîte.

<ol>
	<li>OpenStax. (2019). Physique universitaire Vol. 1. [Version Web]. Récupéré de <a href="https://openstax.org/books/college-physics-2e/pages/4-5-normal-tension-and-other-examples-of-forces">https://openstax.org/books/college-physics-2e/pages/4-5-normal-tension-and-other-examples-of-forces</a></li>
</ol>

tension

La tension est une force le long de la longueur d'un milieu, en particulier, une force portée par un milieu flexible, tel qu'une corde ou un câble. Le mot "tension" vient du latin, signifiant "étirer". Par coïncidence, les cordes flexibles qui transmettent les forces musculaires à d'autres parties du corps sont appelées tendons. Tout connecteur flexible, comme une corde, une corde, une chaîne, un fil ou un câble, ne peut exercer qu'une traction parallèlement à sa longueur; donc, une force portée par un connecteur flexible est une tension avec une direction parallèle au connecteur. Il est important de comprendre que la tension est une traction dans un connecteur. Considérez l'expression "on ne peut pas pousser une corde"; la force de tension ne tire que vers l'extérieur le long des deux extrémités d'une corde.

Les connecteurs flexibles sont souvent utilisés pour transmettre des forces autour des coins, comme dans un système de traction hospitalier, une articulation du doigt ou un câble de frein de vélo. S'il n'y a pas de frottement, la tension est transmise sans diminution. Seule sa direction change, et elle est toujours parallèle au connecteur flexible. Par exemple, les tendons dans le doigt transmettent la force des muscles à d'autres parties du doigt, changeant généralement la direction de la force mais pas son ampleur. Les tendons sont relativement exempts de frottement. De même, un câble de frein sur un vélo transporte la tension des guidons au mécanisme de freinage. Encore une fois, la direction, mais pas l'ampleur, de la force de tension est modifiée.

Tension

La tension est une force sur toute la longueur d’un milieu, en particulier une force portée par un milieu souple, tel qu’une corde ou un câble. Le mot « tension »...

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tension in ropes and strings

Tension is the pulling force carried by a rope, string, or cable when it is stretched by a load. In physics, this force acts along the length of the object and pulls away from the objects at each end.

A stretched rope can support a hanging mass because the tension in the rope balances the weight of the load. The same idea appears in many everyday situations, such as a cable holding a sign or a string lifting an object.

Understanding tension helps students connect force diagrams to real motion. It also shows how forces are transmitted through flexible materials in simple systems.

Tension in Ropes and Strings

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Tension is the pulling force carried by a rope, string, or cable when it is stretched by a load. In physics, this force acts along the length of the object and pulls away from the objects at each end. A stretched rope can support a hanging mass because the tension in the rope balances the weight of the load. The same idea appears in many everyday situations, such as a cable holding a sign or a string lifting an object. Understanding tension helps students connect force diagrams to real motion.

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Learn how tension acts in ropes, strings, and cables as a pulling force that supports loads and balances weight in everyday physics examples.

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Tension in Ropes and Strings

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