Explain Fundamental Forces in Nature (Class 11 – Physics) – Notes
The most curious mind out of all the species is the mind of homosapiens. Humans are always curious about the nature around them and the magic laws on which it functions. The sun always rises in the east and sets in the west, the moon appears at night and the sun appears in the day, and so on. All thRead more
The most curious mind out of all the species is the mind of homosapiens. Humans are always curious about the nature around them and the magic laws on which it functions. The sun always rises in the east and sets in the west, the moon appears at night and the sun appears in the day, and so on. All these questions not on make humans curious but make them think and discover about the different theories of nature and by doing so, humans soon started discovering physics in order to discover the world and its mystery. Let’s learn what is physics in more detail,
What is Physics?
The word “science” has been originated from a word in the Latin dictionary named “Scientia” which means “to know”. Therefore, in one way, it can be said that science is nothing but to know the working of everything, from nature to machines. Under science, a category well known is nature science, which is the study of the physical world around humans. Physics, chemistry, biology, geology, all these fields lie under nature science.
A basic discipline of nature sciences is physics. Physics is also a word taken from the Latin dictionary which means nature. In Sanskrit, it is known as “Bhautiki” which is the physical world around. The definition of physics is not accurately present but it can be said that physics is the study of all basic laws of nature and their manifestation in a different phenomenon.
Physics as a whole explains the diverse physical phenomenon with respect to concepts and laws. For instance, from the falling off an apple on the ground and the law associated with it to the revolving of planets around the sun, to electromagnetism and its effects, physics defines it all. The major concept involved in physics is the use of basic approaches for bigger and complex problems, the process of solving a complex problem by breaking them into smaller parts is called reductionism. Then the act of unifying different laws is called unification.
History of Physics
The word science has been originated from a Latin word named “Scientia” which means “to know”. The word “Physics” has been originated from a Greek word named “Phusike” which means nature. In Sanskrit, physics is called “Vigyaan” which means “knowledge”, all of these words simply tell that physics is as old as the human species. Early civilizations like Egypt, India, Greece, etc, made a significant contribution in the field of physics. From the 16th century, Europe participated heavily and contributed. By the mid-twentieth century, science became an international enterprise and the rapid growth in the very field is on. The two major approaches in physics are already described above, they are unification and reductionism.
Importance and application of physics
- The complex and bigger magnitude identities are explained using simpler theories.
- New devices are invented using the basic physics laws.
- The observations and experiments can be used to create new laws or to modify the existing laws.
- The ultimate aim is to find a unified set of laws that govern matter, energy, motion at both microscopic and macroscopic levels.
Scope and Excitement of Physics
The scope of physics can be majorly understood by looking at its sub-divisions. There are basically two types of studies in physics, macroscopic physics, and microscopic physics. Macroscopic physics deals with phenomena on a terrestrial, astronomical scale, while microscopic physics deals with the phenomenon on an atomic, molecular, or nuclear scale. The macroscopic study is done mostly in classical physics that includes subjects like mechanics, thermodynamics, etc. The microscopic study is the study of the structure of the atom, etc. Classical physics is unable to contribute in this field and currently, quantum theory is referred for the microscopic level studies.
Therefore, it can be said that the scope of physics is really very vast. The study covers a plethora of physical quantities like length, mass, time, energy, etc. From the study of smallest quantities (ranging up to 10-30 or less) to the study of the quantities on an astronomical level (ranging up to 1020 or more).
Fundamental forces in Nature
Force is seen and experienced on a daily basis and is available on both macroscopic and microscopic levels. At a macroscopic level, apart from gravitational force, several kinds of forces are experienced, for instance, muscular force, contact forces, the elongation or compression of elastics, etc. On a microscopic level, there are electric and magnetic forces, nuclear forces, etc. Although, it was further observed that most of the forces defined or explained are derived from four fundamental forces. The four fundamental forces in nature are,
- Gravitational Force: It is the mutual force that occurs between two objects by the virtue of their masses. Gravitational force is a universal force. The formula for gravitational force is,
FG = (G M1M2)/r2
FG = Gravitational force
M1, M2 = Masses1 and 2.
r = distance between the center of the masses.
- Electromagnetic force: It is the force that occurs between the charged particles. If the charges are at rest, the phenomenon of electric field occurs and if the charges are moving, both electric and magnetic field phenomenon occurs. Therefore, it is named electromagnetic force.
- Strong nuclear force: It is the strongest force among all four fundamental forces. This force binds the protons and neutrons in a nucleus. This force is charge independent, that is, it acts on proton-proton, proton-neutron, etc.
- Weak nuclear force: Weak nuclear force is not the weakest force among fundamental forces. It is not as weak as a gravitational force but is weaker than the electromagnetic force. This force is observed in only some nuclear processes, for example, β-decay of the nucleus.
Conceptual Questions
Question 1: Which of the four fundamental forces is the weakest and the strongest?
Answer:
The weakest force in nature is the gravitational force and the strongest force in nature is the strong nuclear force.
Question 2: What are the laws of conservation in nature?
Answer:
Following are the laws of conservation in nature:
- Law of conservation of mass.
- Law of conservation of energy.
- Law of conservation of momentum.
- Law of conservation of charge.
Question 3: On what two things the scope of physics is defined?
Answer:
The two things on which the scope of physics is defined are unification and reductionism. Unification is the physics of unifying all laws. Whereas, reductionism is the process of solving complex problems by breaking them into simpler parts.
Question 4: What part of the study is not handled by the classical study of physics?
Answer:
The microscopic study of the physical world is not handled by classical physics. A new field termed quantum theory handles the study of physics at the microscopic level.
Question 5: Give an example of a weak nuclear force.
Answer:
See lessThe weak nuclear force is observed in a few nuclear processes. An example of a weak nuclear force is the β-decay of the nucleus.
Fundamental Forces The most beautiful phenomenon that can be seen in physics is that how universe is so disciplined and synced together. The force has kept the universe bind together. Forces have always played an important role in the human existence, but it is not realized by humans. Human beings cRead more
Fundamental Forces
The most beautiful phenomenon that can be seen in physics is that how universe is so disciplined and synced together. The force has kept the universe bind together. Forces have always played an important role in the human existence, but it is not realized by humans. Human beings constantly experience some force acting on them like gravitational force, etc. There are some forces that naturally exist in the universe, they are known as Fundamental Forces. Let’s learn about them in some detail.
Force
Force is an interaction, either with contact or without contact. When there is no opposition given to the Force, It can result in changing the motion, shape, position, of a body. Whenever some interaction occurs between two objects, there is a certain force acting upon them. There are many types of Forces present, For instance, Applied Force, Gravitational Force, Frictional Force, Tension Force, etc.
Fundamental Forces in nature
These forces are so well-defined that they cover the macroscopic and microscopic forces present in nature. The forces learned or seen by humans in everyday life, from frictional force, pull, push, thrust, etc. are known as derived forces, and they are not considered the fundamental forces. The derived forces are actually derived from the fundamental forces in some way or the other. Some Fundamental Forces are,
These above-mentioned forces are responsible for all the observations obtained in forces present in the nature.
Gravitational Force
This force exists by the virtue of the masses of any objects. Gravitational force is the mutual force of attraction between two masses. Attraction between any mass and Earth is called Gravity. Isaac Newton first gave the concept of gravity. Gravity is the most intuitive and the weakest force present in nature. The Irony is that Gravity actually holds the planet, Solar system, Entire Universe together, yet it is known to be the weakest force present in nature.
Electromagnetic Force
Charges when they are at rest exert a force at each other known as the Electric force of attraction/repulsion. Like charges repel each other while unlike charges attract each other. When charges start to move and become dynamic, they develop magnetic field lines around and have magnetic force, these two forces combined are known as Electromagnetic forces present in nature.
Magnetic force produced by current (moving charge)
Combining the above two forces which are always perpendicular to each other will give rise to Electromagnetic Force. The force is produced by massless bosons and photons present in the charges, Electromagnetic force exists in nature and is responsible for many derived forces we experience every day, for example, Friction Force, Normal Force, Elasticity, and so on.
It is the force of attraction between Protons and Neutrons. The force is the same whether protons and protons are present or neutrons and neutrons are present or protons and neutrons are looked at. In short, a Strong nuclear force exists between all nucleons. In short Ranges, this Force is the strongest among all the forces. It is important to note that at a distance of 10-13 cm, this force vanishes.
Weak Nuclear Force
This Force is seen In the β Decay of a nucleus. Scientist named Wolfgang Pauli First predicted a particle named Neutrino. The Neutrino is an uncharged Particle that is released along with the electron in the β Decay process. During β Decay, when Beta Particle is ejected from an Atom, it tends to accelerate away from the atom and some force is required to accelerate the particle known as Weak Nuclear Force. Weak Nuclear Force is stronger than gravitational force but weaker than a strong nuclear force.
Table to represent Range and Relative Strength of Different Forces:
Conceptual Questions
Question 1: Which Fundamental Force is the strongest and weakest among the fundamental forces present in nature?
Answer:
Question 2: Which of the following forces are Fundamental, and which are derived in nature?
Weak Nuclear Force, Friction Force, Gravity, Elasticity, Electromagnetic Force, Push
Answer:
Question 3: A statement is being used now “Gravity is not a force” Throw light on this statement.
Answer:
Question 4: If the masses of 2 objects are doubled and the space between them is also doubled. How will the gravitational Force between them change?
Answer:
Question 5: What are Pseudo Forces? Give Examples.
Answer:
Question 6: Which two forces have infinite range?
Answer: