Strong Force

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Strong Interaction

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The strong interaction is among the four known basic fundamental interactions in nuclear physics and particle physics and is necessary for strong nuclear force. The strong force is roughly 137 times stronger than electromagnetism, a million times stronger than the weak interaction, and 1038 times stronger than gravity at a scale of 10-15m (1 femtometer). As it confines quarks into hadron particles like the neutron and proton, the strong nuclear force keeps much ordinary matter united.

The strong force also brings these neutrons and protons together to form atomic nuclei. The strong force field energy accounts for the majority of the density of a proton or neutron; each of the quarks accounts only for approximately 1% of a proton's mass.

The strong interaction can be seen at two different ranges and is handled by two different force carriers. This is the force that holds protons and neutrons (nucleons) with each other to create the atomic nuclei on a greater scale (roughly 1 to 3 fm). It is the force that keeps quarks with each other to produce protons, neutrons, as well as other hadron particles on a lesser scale.

Four Fundamental Forces

Physical forces act everywhere, from walking down the street to shooting a satellite into space to placing a magnet on your fridge. However, all of the forces that we encounter daily (and many that we aren't aware we encounter daily) can be reduced to only 4 fundamental forces.

Below mentioned are the 4 fundamental forces of nature:-

  1. Gravity. 

  2. The weak force. 

  3. Electromagnetism. 

  4. The strong force. 


Gravity is the attraction amongst two-mass or energy objects, such as a rock falling from a highway, planets orbiting, or the moon producing ocean tides. Gravity has been the most natural and well-known of the fundamental forces, but it's also one of the most difficult to understand.

The concept of gravity was first proposed by Isaac Newton, who was allegedly motivated by an apple falling to the ground.  Gravity, he explained, is a physical attraction present in between two objects. Hundreds of years later  Albert Einstein proposed, via his theory of general relativity, that gravity is neither an attraction nor a force.

Weak Nuclear Force

Particle decay is caused by the weak force, also known as the weak nuclear force. This is when one kind of subatomic particle transforms into the other kind. A neutrino that gets too close to a neutron, for example, may turn the neutron into a proton whereas the neutrino transo an electron.

This interaction is described by physicists as the exchange of force-carrying particles known as bosons. The weak force, electromagnetic force, and strong force are all caused by different types of bosons. The bosons of the weak force are charged particles known as W and Z bosons. These bosons can be exchanged when subatomic particles like protons, neutrons, and electrons arrive within 10-18meters, or 0.1 per cent of the circumference of a proton, of each other. As a consequence, the decay of the subatomic particles and are replaced by new ones.

Electromagnetic Force

The Lorentz force, also known as the electromagnetic force, operates among charged particles such as positively charged protons and negatively charged electrons. Like charges tend to repel each other, whereas opposite charges attract each other. The force is proportional to the charge. This force can be experienced from an infinite distance, just like gravity.

The electromagnetic force is made up of two distinct parts, namely, the electric force and the magnetic force, as its name suggests. Physicists initially thought of these forces as separate entities, but later discovered that they are all elements of the very same force.

The electric component acts within charged particles, if they're moving or not, forming a field wherein the charges may interact. When those charged particles are set in motion, meanwhile, they begin to exhibit the second component, the magnetic force. Further, when they move, the particles produce a magnetic field surrounding them.

Strong Nuclear Force

The strongest force in nature is the strong nuclear force, also known as the strong nuclear interaction. From the strong nuclear force definition, it is known that It is very much more powerful than gravity. That's because it brings together the smallest particles of matter to form bigger ones. The strong force binds the quarks that comprise protons and neutrons collectively, and it also brings the protons and neutrons of an atom's nucleus around each other.

The strong force, like the weak force, is only active when subatomic particles are incredibly close to each other. They must be within 10 to 15 metres of one another or approximately the diameter of a proton. However, unlike most of the other fundamental forces, the strong force becomes weaker as subatomic particles come nearer together. When the particles are the furthest apart from one another, it reaches its maximum strength. 

Gluons are massless charged bosons that convey the strong force among quarks and maintain them "glued" around each other once they are within reach. The residual strong force operates in between protons and neutrons and is a small fraction of the strong force. Because of the similar charges, protons in the nucleus repel one another, but the residual strong force overcomes this repulsion, keeping the particles locked in the nucleus of the atom.

Intermolecular Forces

Intermolecular forces (IMF) (also known as secondary forces) are the forces that prevent particles from interacting with each other in molecules. They include forces of attraction and repulsion that act between atoms and other kinds of adjacent particles, such as atoms or ions. In comparison to intramolecular forces that maintain a molecule intact, intermolecular forces are weak. The different types of intermolecular forces are Hydrogen bonding /H-bonding, Ionic bonding, Ion–dipole forces, Debye force, van der Waals forces – Keesom force, and London dispersion force.

The strong intermolecular forces are ion-dipole and the second-highest strong intermolecular forces are hydrogen bonding. 

FAQ (Frequently Asked Questions)

1. What Makes a Force More Powerful?

Ans. The gauge colour charge of the particle, a collective theoretical property, influences the strength. Within quarks, the strong force operates. The strong force, unlike most other forces (electromagnetic, weak, and gravitational), does not weaken with a varying range between quark pairs.

2. Which Country Has the Smallest Gravitational Pull?

Ans. Sri Lanka has the smallest gravitational pull.