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Fundamental Forces in Nature - Gravitational, Electromagnetic, Strong Nuclear, Weak Nuclear Forces
IMPORTANT LINKS
Physical World
The Four Pillars of Nature's Forces
The universe as we know it is held together by four essential forces. These forces are integral to the existence and structural integrity of all matter. In terms of physics, a force is defined as a push or pull that alters an object's state of motion or form. Sir Isaac Newton defined force as a factor that causes an object with mass ‘m’ to move with an acceleration ‘a’. The four fundamental forces of nature are:
- Gravitational force
- Electromagnetic force
- Strong nuclear force
- Weak nuclear force
Let's dive into a brief understanding of these four fundamental forces.
Gravitational Force Electromagnetic Force Strong Nuclear Forces Weak Nuclear Forces
Gravitational Force
Ever wondered why we don't see floating humans, cows, cars and other objects all around us? It's all thanks to the gravitational force of the Earth that keeps us grounded. Gravitational force is the force that keeps planets in their orbits and it acts over an infinite range.
Exploring Gravitational Force
Gravitational force is one of the four fundamental forces of nature. It is the weakest among the four but plays a crucial role as an attractive force resulting from gravitational interaction.
Newton’s law of gravity states that the gravitational force between two bodies is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
For large objects, like the Sun or giant planets, gravitational force is considered strong due to their large masses. However, at the atomic level, this force is considered weak.
The Formula for Gravitational Force
Gravitational force can be represented as follows:
In this equation,
- F g represents the gravitational force
- G is the universal gravitational constant
- m 1 and m 2 are the masses of the objects being considered
- r is the distance between the centres of the two objects being considered
Earth's Gravitational Force
The gravitational force of the Earth is 9.807 m/s 2 .
Examples of Gravitational Force
- An apple falling from a tree due to Earth's gravitational pull.
- The tides in the ocean caused by the gravitational force between the Earth and the Moon.
Electromagnetic Force
It's fascinating to know that we haven't actually touched anything in our lives. All matter, including us, is made up of atoms, which have a dense nucleus, protons, neutrons, and electrons. Electrons, which carry a negative charge, occupy the outermost layer of an atom. As per their nature, particles are attracted to particles with an opposite charge and repel those with similar charges.
When you reach out to hold a pen, the electrons in your body and the pen repel each other. Thus, technically, you never really touch anything!
These interactions are governed by electromagnetic forces. These forces are also responsible for phenomena like the charging of a comb when you brush your hair, or the holding together of subatomic particles.
Electromagnetic forces have a long range, but their effect diminishes over distance due to the shielding effect. However, at a subatomic level, these forces are considered strong but still weaker than strong nuclear forces.
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Strong Nuclear Forces
Among the four fundamental forces, nuclear forces are the strongest. They are responsible for holding the nuclei of atoms together. Despite the presence of electromagnetic forces, the nucleus of an atom doesn't disintegrate. This is because nuclear forces, which are stronger than both gravitational and electromagnetic forces, are at play.
This force is so strong that it binds protons with similar charges within the nucleus. It is mostly attractive in nature but can sometimes be repulsive. It has a very short range of just 1 femtometre (fm).
Weak Nuclear Forces
Weak nuclear forces exist between elementary particles and are responsible for certain low-probability processes.
An Example of Weak Nuclear Force
Weak nuclear forces are responsible for radioactive decay , specifically beta decay and neutrino interactions. It has a very short range (less than 1 fm) and is, as the name suggests, weak in nature.
Key Features of Weak Force
Here are some properties of weak force:
- Weak nuclear force is the only force that does not adhere to parity-symmetry.
- It is the only force that does not follow charge-parity symmetry.
- Weak nuclear force is responsible for the transformation of one type of quark into another.
- The propagation of weak force is carried out by particles with significant masses.
What is Nuclear Force?
Frequently Asked Questions
Name the factors affecting the value of acceleration due to gravity.
Following are the factors affecting the value of acceleration due to gravity: Height from the earth’s surface, Latitude of the plane, Depth.
What is the distance between the two protons to attract each other?
The distance between the two protons should be 10-15 cm so that they attract each other.
Name the force responsible for existence of the protons in the nucleus of an atom.
Protons are existing in the nucleus of an atom because of the strong attractive nuclear force which binds them with each other.
What is Ampere law?
Ampere law is also known as Ampere circuital law which states that the closed integral of the magnetic field intensity is the same as the current enclosed by it.