The 20 types of force (according to physics)

The concept of force has a large number of denotations in different fields, being in some synonymous with strength both physically and mentally, resilience and resistance to events.

But beyond that, we also call force one of the main magnitudes of physics, studied from physics basic even in the most complex branches of science, and that participates in a large number of phenomena, actions and reactions.

So that, At the physical level we can talk about different types of force, about which we are going to make a brief mention in this article.

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What do we call strength?

Before starting to talk about the various typologies or categories that have been established at the time To analyze different types of force, it is necessary to establish a brief definition of the concept.

In a generic way we can define the force as a physical quantity of vector type, to which it is associated and considered the cause of the ability to generate a displacement or movement with acceleration by a body or object, a modification in its structure or even its state of rest when in order to reach it a resistance must be exerted to another force. In order to be correctly defined, it should be noted that every force has a point of application, a specific direction and intensity that will determine the final behavior of the object.

how magnitude that is force has a unit of measure, the Newton (in honor of Isaac Newton, who is considered the first to establish a mathematical formula for his calculation), which makes refers to the amount of force necessary to generate an acceleration of one meter per second squared in a body of one kilogram of mass In addition, there are also other units of measurement, such as the dyne.

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types of force

It is possible to classify the types of force following different criteria. Let's see them.

1. Depending on specific parameters

We can find classifications made based on aspects such as their permanence, the existence or not of direct contact between the bodies or their way of acting. Examples of this are the following types of force.

1.1. fixed forces

Fixed or permanent forces are understood to be all those inherent in the body or object itself and that derive from its structure or configuration, and from which it is not possible to escape. One of the most easily visible is the weight, product of the mass of the body and the gravitational attraction to which it is subjected.

1.2. variable forces

Also called intermittent, are those forces that are not part of the structure of the object or body in which the movement or change occurs but rather comes from other bodies or elements. An example would be the force applied by a person to a car to move it.

1.3. Contact

Contact forces are understood to be all those that are characterized by the need for contact between bodies or elements in order to generate movement or structural change. It's all about the forces traditionally worked by classical mechanics, as we will see later.

1.4. From distance

Contrary to the previous case, the forces at a distance are all those in which it is not necessary for there is a contact between the bodies to achieve an alteration of the structure or a displacement of the bodies. An example of this would be electromagnetism..

1.5. static

All those forces that do not vary in intensity, direction or place, remaining practically constant whenever they exist, are called static. An example would be the force of gravity.

1.6. dynamics

Dynamic forces are all those in which the general values ​​that are part of the force vary constantly and abruptly, changing its direction, place of application or intensity.

1.7. Of action

This name is given to those forces that are applied to an object in order to move it or modify its structure, not arising from the object itself but from some external element. The act of pushing something would imply applying an action force.

1.8. of reaction

All those that are generated by the body itself are called as such. in response to the application of an external force, from a given point of application. In the previous case, the moved body would be exerting a reaction force towards us.

1.9. balanced

They are understood as such those forces that oppose each other having the same intensity but whose directions are completely opposite, something that causes the body in question to remain in a specific position. This type of force would be exemplified by any object sitting still on the ground or by two people of the same strength pushing each other at the same time.

1.10. unbalanced

We refer to those forces that when applied to a specific body, they generate its movement, as there is no balance or a sufficient counterforce to prevent it.

2. In classical mechanics: contact forces

There are many and diverse types of force that we can find in nature, but generally when it begins to be studied physically The concept of force is usually used in the context of classical mechanics, referring to a type of forces called contact. Within these we can find the following types of force.

2.1. normal

We understand as normal force that force that is exerted by the interaction between two bodies in contact, such as an object and the ground, exerting a reactive force to the weight which would go in the opposite direction to the weight.

2.2. applied

As applied force we understand that force that a body uses on another and that causes an accelerated movement or a change in the structure of the object. It is a direct contact force.

23. Friction

The friction or force of friction is that force that appears before the contact of two bodies and that acquires a direction directly opposite to the applied or normal force. For example, when pushing an object, it offers resistance produced to a large extent by the force of friction against the ground.

Another analogous form of this type of force, which is sometimes classified independently, is that of air resistance. This force is what explains, for example, that two objects of the same mass thrown at the same time from the same height can take a different time to reach the ground (air friction), or that an object pushed down a slight slope may end up holding back

2.4. elastic

We call elastic force to that which is produced when a surface or object is held in a position of not balance by a certain force, appearing as a reaction that seeks to restore said initial position or balance. That is, it is the one that occurs when a body subjected to a force that has deformed it try to return to its original state. A typical example can be found in springs, springs or stretched rubbers that seek to return to their original position.

2.5. Strain

We are facing a peculiar type of force, characterized by being able to transmit a force between different bodies and which is generated when two opposing forces pull a body in opposite directions without actually breaking it. It can be used to generate systems that distribute the force to be applied to generate movement. The tension force is that force that allows us to use, for example, pulleys to move heavy objects.

2.6. of inertia

The force of inertia or fictitious force is the one with which a body is moved by the resultant of the forces that are previously applied even when the body or object that generated said force has already ceased to apply it in a way direct. It is the force with which a body maintains its state of motion, in the same direction of acceleration. This is what happens, for example, when in the face of a crash or a sudden deceleration of a car, the body of the occupants tends to project in the same direction than the one the vehicle was following.

3. fundamental forces

In addition to those typical of classical mechanics and related to macroscopic bodies, we can find other great forces that refer to the relationships that the particles of matter between themselves or the existence of forces at a distance, being their study a product mostly of modern physics and allowing to explain a large part of the previous.

3.1. Gravitational force

We call that force gravitational force attraction between objects and whose intensity depends on their masses and the distance between them. The most studied gravitational force is that of the planet itself, which attracts the bodies that exist on it towards its surface, being one of the best-known distance forces. It is also the force that makes planets orbit around stars. It is also important in magnitudes such as weight.

3.2. electromagnetic force

Although in the past we spoke separately of the magnetic and electrostatic forces, the progressive study of the properties of these forces have shown that they are in fact interrelated.

It's all about strength through which electrical particles are attracted to or repelled by other charged particles either with the opposite sign (attractive force) or with the same one (repulsion). When these relationships occur in moving particles, electromagnetic fields are generated.

3.3. weak nuclear force

Probably some of the most difficult forces for those unversed in physics to understand is the nuclear force. In the case of the weak nuclear force, we are dealing with a type of force which allows the decay of neutrons and radioactivity. In addition to generating forces of attraction and repulsion, it allows a particle to change.

3.4. strong nuclear force

Coming from particle physics, the strong nuclear force is one that allows two particles that due to electrical charge should repel each other to remain united, something that allows the existence of a nucleus of protons in most molecules.