Classical mechanics is the branch of physics that studies the motion of bodies and is divided into three main areas: kinematics, dynamics and static. Its origins are very ancient because they are connected to the life of man on earth.
Men have always tried to understand the functioning of the world around them and still physics continues to seek answers to the natural phenomena of our universe.
Given its strong connection with reality, classical mechanics explains various phenomena of everyday life. Precisely for this reason it is a fundamental part of the school physics program.
Any address of frequent studies there are some topics of classical mechanics that you cannot miss. Find out what they are!
History of mechanical physics
Human beings have always tried to understand natural phenomena!
Since ancient times, humans have observed the phenomena of nature in order to exploit them to their advantage. The history of physics is therefore very ancient!
In Ancient Greece, perceptions of movement have become the subject of systematic studies. The great scholars of the time sought explanations on the phenomena of everyday life. The philosophy remains the reference science in this period, but at the same time lay the foundation for the birth of today’s science: biology, mathematics, physics …
In the Renaissance, studies began to focus on the laws that govern the universe through observation and experimentation. Nicolò Copernico revolutionized the Aristotelian system, affirming that the Sun and not the Earth was at the center of the universe.
From his heliocentric theory developed the studies of Galileo Galilei who gave further impetus to astronomy.
With the publication of the Mathematical Principles of Natural Philosophy , Isaac Newton laid the foundations of classical mechanics with the laws on dynamics and the law of universal gravitation.
Thanks to classical physics, mechanics has been able to develop in the twentieth century by taking giant steps leading to Albert Einstein’s relativistic mechanics and quantum mechanics. Without the great physicists of the past and present, agencies like NASA would not exist!
What does mechanics study?
One of the main topics of the physics program in high school is classical mechanics . This branch of physics studies the motion of objects and their behaviors, determining specific factors such as the strength, acceleration, position and speed of bodies.
Thanks to this science we can understand the laws that regulate any type of motion, such as that of blood flow, planets or tectonic plates.
Mechanics is divided into three areas: classical, relativistic and quantum . Classical mechanics studies the natural events of everyday life, relativistic mechanics the bodies that have a speed similar to that of light, quantum mechanics analyzes the motions in the internal part of the atom.
If you are preparing for the high school exams, you need to know the basic concepts of mechanics!
What does kinematics study?
Mechanics is an integral part of the physics program for high school!
Kinematics studies the motion of bodies, without analyzing their causes. In particular, kinematics studies the acceleration, velocity and displacement of a body, without taking into consideration the forces applied to the body or its mass.
The kinematics focuses on different types of motion, such as circular and linear motion, uniform rectilinear motion and uniformly accelerated rectilinear motion. It is divided into scalar kinematics, which studies motions without taking direction and direction into consideration and vector kinematics, which looks at the orientation of motion.
With kinematics you can calculate the speed a car travels, the time it takes for a taxi to reach its final destination, the acceleration of an athlete …
Due to its implications in everyday reality, kinematics is one of the first subjects of physics in high school.
Dynamics and Newton’s laws
Dynamics is a part of mechanics that studies the motions of bodies starting from their causes. The origins of this discipline can be traced back to Isaac Newton, the scholar who systematically investigated the motion of bodies. Building on the previous works of Galileo Galilei and Giovanni Keplero, Newton developed the fundamental principles of dynamics .
Newton’s first law
Newton’s first law, better known as the principle of inertia, states that a body in a state of quiet or in uniform rectilinear motion tends to maintain its state unless a force is exerted on it that forces it to change state.
Newton’s second law
Newton’s second law, or fundamental principle of dynamics, states that a force applied on a body is equal to the product of acceleration for mass. The equation that represents it is F = ma, where F is the force, m the mass and the acceleration.
Newton’s third law
If a body X exerts a force on a material point Y, it reacts by opposing a force equal and opposite to that of the body X. Newton’s third law is also known as the principle of action and reaction.
Static and hydrostatic
Static and hydrostatic study the state of equilibrium of fluids!
What do hydrostatics and statics study ? Hydrostatics is the branch of mechanics that studies fluids in a quiet state. The reference figure is Archimedes, the Greek scholar who made several experiments to understand the behavior of fluids .
Archimedes’ push is a principle that we can experience in everyday life and expresses a very simple concept:
“A body immersed in a liquid will receive a push towards the other of the same weight as the fluid moved.”
If you have a Galileo Galilei scale at your disposal, you can also want to see how a body immersed in a liquid behaves, depending on its weight. If the thrust of the liquid is greater than the weight of the body, it undergoes an upward acceleration. If the weight of the body is less than that of the thrust, the body will have a downward acceleration.
By taking advantage of the hydrostatic pressure , we can make machines that allow us to produce a great deal of force by pressing on the surface of a liquid.
The Pascal principle states, in fact, that the pressure that is exerted on one point of a fluid is transmitted with the same intensity to every other point of the fluid.
Static is the branch of mechanics that studies bodies in a quiet state . The absence of movement is equivalent to zero acceleration, that is, a condition in which the forces acting on a body are in balance. In statics, the vector sum of the forces exerted on a material point is zero.
With statics we can evaluate the equilibrium conditions of very large and very small bodies by distinguishing three types of equilibrium:
- Stable balance, the body tends to return to its normal state of balance even if there are disturbances in the system.
- Unstable equilibrium, even the slightest disturbance is enough to alter the state of equilibrium of the bodies.
- Indifferent balance, the bodies remain in a state of inertia, regardless of the type of force that is exerted
Universal gravitation
What is the principle of free fall of bodies?
The universal law of gravitation was developed by Isaac Newton and explains the attraction force that exists between two bodies with mass. This force is as if it were an imaginary line that unites the bodies.
According to the law of universal gravitation :
“Two bodies with mass attract each other with a force directly proportional to the product of the masses and inversely proportional to the square of the distance that separates them.”
Newton managed to demonstrate Kepler’s laws on elliptical orbits, the speed of the planets. The universal law of gravitation allows to determine the radius and mass of the stars, the periods of asteroids and astronomical events.
According to a legend, Newton had the intuition about gravity by observing the fall of an apple from the tree. The universal law of gravitation was fundamental for subsequent theories on relativity and quantum mechanics.
Knowing classical physics is therefore important for understanding the latest discoveries in physics such as the black hole. Physics, then, is one of the subjects of study in high school and for those enrolled in the scientific high school it is also an exam subject.
The second written test for the scientific high school is in fact the test of mathematics and physics. Students must solve a problem of their choice and answer four of the eight questions prepared by the ministry.
If you think about enrolling in the physics faculty, take advantage of the general review you do for your baccalaureate exams because you will need it to face the self-assessment tests at the university .
It is a math, logic and science test that you need to understand your starting level, and at university to find out if you need to deepen your scientific knowledge before moving on to the regular study plan.
Whatever the reason why you study physics, remember that it is closely related to mathematics, so never underestimate the formulas. Take advantage of its practical nature to experiment and better understand concepts such as acceleration, balance, strength.
