Name: types of forces in physics
Uploaded: 2025-05-22T09:06:01.000Z
Duration: 1 min 22 s
Channel: JoVE

Les forces peuvent être classées en fonction de leur origine en forces de contact et sans contact.
Les forces qui nécessitent un contact physique entre deux objets sont appelées forces de contact. Les forces de frottement, de tension et normales sont des exemples de forces de contact.
Les forces qui peuvent agir sur un objet sans aucun contact physique entre l’objet et la source sont appelées forces sans contact. Les forces gravitationnelles, magnétiques et électrostatiques sont des exemples de forces sans contact.
De plus, les forces peuvent être classées comme des forces concentrées et distribuées.
Une force concentrée est une force qui agit en un point spécifique sur un objet, tandis qu’une force distribuée agit sur toute la surface ou le volume d’un objet.
La force gravitationnelle agissant sur la surface supérieure d’un corps est légèrement inférieure à la force agissant sur la partie inférieure du corps. Mais, conventionnellement, on suppose que la force gravitationnelle agit au centre de gravité du corps.

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

classification des forces

Force Classification

Les forces jouent un rôle crucial dans l'étude de la physique et de l'ingénierie. Elles sont essentielles pour décrire le mouvement, le comportement et l'équilibre des objets dans le monde physique. Les forces peuvent être classifiées en fonction de leur origine, de leur type et de leur direction d'action. Les forces de contact et les forces sans contact sont deux des catégories de forces les plus largement utilisées. Comme leur nom l'indique, les forces de contact nécessitent un contact physique entre deux objets pour agir l'une sur l'autre. Les exemples de forces de contact comprennent les forces de friction, de tension et normales qui résultent du contact de surface. En revanche, les forces sans contact peuvent agir sur un objet sans aucun contact physique entre l'objet et la source. Les exemples de forces sans contact comprennent les forces gravitationnelles entre les corps célestes, les forces magnétiques entre deux aimants et les forces électrostatiques qui provoquent l'attraction ou la répulsion entre les particules chargées. Une autre façon de classer les forces est basée sur leur répartition. Une force concentrée est une force qui agit en un point spécifique sur un objet. Un exemple de force concentrée est un marteau frappant un clou. Lorsque le marteau frappe le clou, il exerce une force concentrée au point de contact entre le marteau et le clou. À l'inverse, les forces distribuées agissent sur toute la surface ou le volume d'un objet. Ces forces peuvent être classées comme uniformes ou non uniformes, selon que la force est la même en tous points de l'objet. Les exemples de forces distribuées comprennent la force exercée par un fluide uniforme qui agit sur la surface d'un corps, la résistance de l'air qui agit sur les véhicules se déplaçant dans l'air et la force exercée par la main d'une personne sur une table. La classification des forces est un concept important en génie mécanique car elle permet aux ingénieurs de comprendre et de prédire le comportement des structures et des machines sous diverses charges.

Classification des forces

Les forces jouent un rôle crucial dans l’étude de la physique et de l’ingénierie. Ils sont essentiels pour décrire le mouvement, le comportement et l’équilibre des objets dans ...

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types of forces in physics

Forces in physics can be grouped by how they act and where they come from. These groups help describe motion, behavior, and equilibrium in the physical world. They are also useful in physics and engineering.

One common way to classify forces is by whether they need contact. Contact forces act only when two objects touch. Frictional force, tension, and normal force are all contact forces that come from surface contact.

Forces can also act without physical touch. These are called non-contact forces. Gravitational force acts between celestial bodies, magnetic force acts between two magnets, and electrostatic force can cause attraction or repulsion between charged particles.

Another way to sort forces is by how they are spread over an object. A concentrated force acts at one specific point. A hammer striking a nail is a clear example because the force is applied at the point of contact.

Distributed forces act over a surface area or through a volume. They may be uniform or non-uniform, depending on whether the force is the same at every point. Examples include the force from a uniform fluid on a body, air resistance on vehicles moving through the air, and the force a person’s hand exerts on a table.

Force classification matters in mechanical engineering. It helps engineers understand and predict how structures and machines respond to different loads.

Types of Forces in Physics

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force classification

Forces in physics can be grouped by how they act and where they come from. These groups help describe motion, behavior, and equilibrium in the physical world. They are also useful in physics and engineering. One common way to classify forces is by whether they need contact. Contact forces act only when two objects touch. Frictional force, tension, and normal force are all contact forces that come from surface contact. Forces can also act without physical touch. These are called non-contact...

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two-dimensional-force-system-problem-solving

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scalar notation

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Using the Dot Product to Solve Vector Questions

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cross product

Cross Product Direction and Magnitude

The cross product is a vector operation in vector algebra that creates a third vector from two input vectors. Unlike the scalar product, it does not give a single number. The result is a vector perpendicular to both original vectors. The size, or magnitude, of the cross product depends on the magnitudes of both vectors and the sine of the angle between them. A larger angle between the vectors gives a larger cross product magnitude. The direction is found with the right-hand rule. If the...

key terms and concepts

Learn how forces are classified as contact, non-contact, concentrated, and distributed, with real examples from physics and engineering.

Types of Forces in Physics | 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.

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Types of Forces in Physics

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