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

Forces can be classified based on origin as contact and non-contact forces.
The forces that require physical contact between two objects are known as contact forces. Frictional, tensional, and normal forces are examples of contact forces.
The forces that can act on an object without any physical contact between the object and the source are known as non-contact forces. Gravitational, magnetic, and electrostatic forces are examples of non-contact forces.
Further, the forces can be classified as concentrated and distributed forces.
A concentrated force is a force that acts at a specific point on an object, whereas a distributed force acts over the entire surface area or volume of an object.
The gravitational force acting on the top surface of a body is slightly less than the force acting on the bottom of the body. But, conventionally, it is assumed that the gravitational force acts at the center of gravity of the body.

force classification

Forces play a crucial role in the study of physics and engineering. They are essential in describing the motion, behavior, and equilibrium of objects in the physical world. Forces can be classified based on their origin, type, and direction of action.
Contact and non-contact forces are two of the most widely used categories of forces. As the name suggests, contact forces require physical contact between two objects to act upon each other. Examples of contact forces include frictional, tensional, and normal forces that arise due to surface contact. On the other hand, non-contact forces can act on an object without any physical contact between the object and the source. Examples of non-contact forces include gravitational forces between celestial bodies, magnetic forces between two magnets, and electrostatic forces that cause attraction or repulsion between charged particles.
Another way to classify forces is based on their distribution. A concentrated force is a force that acts at a specific point on an object. An example of a concentrated force is a hammer hitting a nail. When the hammer strikes the nail, it exerts a concentrated force at the point of contact between the hammer and the nail. Conversely, distributed forces act over the entire surface area or volume of an object. These forces can be further classified as uniform or non-uniform, depending on whether the force is the same at all points of the object. Examples of distributed forces include the force exerted by a uniform fluid acting on the surface of a body, air resistance acting on vehicles moving through the air, and the force exerted by a person&#39;s hand on a table. Force classification is an important concept in mechanical engineering because it enables engineers to understand and predict the behavior of structures and machines under various loads.

Force Classification

Forces play a crucial role in the study of physics and engineering. They are essential in describing the motion, behavior, and equilibrium of objects in ...

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KEY TERMS AND CONCEPTS

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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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

two-dimensional-force-system-problem-solving

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scalar notation

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cartesian vector notation

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Force Components in 3D Space

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three-dimensional force system:problem solving

three-dimensional-force-systemproblem-solving

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position vectors

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cross product

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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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