In this blog post, we will explore how Newton’s laws affect modern science, technology, and our daily lives, and why they are still important today.
Even people who know nothing about physics would easily name Isaac Newton and Albert Einstein as the two people who have had the greatest influence on modern physics. These two scientists fundamentally changed the paradigm of science through their innovative thinking and discoveries in their respective eras. Isaac Newton laid the foundation for the physics we are currently studying and continue to research, and even today, modern physics cannot stray far from Isaac Newton’s physics. Newton combined experimental observation and mathematical analysis to develop physics into a rigorous science, and his laws are still valid in explaining many phenomena in the natural world. Many people mistakenly believe that Albert Einstein overturned Isaac Newton’s physics, but in fact, Albert Einstein made Newtonian mechanics more complete with his concept of space-time. Albert Einstein’s theory of relativity expanded our understanding of gravity and motion in particular, but this did not negate Newton’s classical mechanics; rather, it served to integrate it into a larger framework. As a result, Isaac Newton’s contributions still occupy an important place in modern physics.
I would like to introduce the three laws of Newtonian mechanics that changed physics and, in fact, changed the way scientists have viewed the world until now. These three laws are not merely the basic principles of physics, but also greatly help explain many phenomena we encounter in our daily lives and form the foundation of modern science and technology.
The first of Newton’s three laws of motion is the law of inertia. It states that when no external force is applied to an object, the object remains in its current state of motion. In other words, when an object is in motion and no external force is applied to it, the direction and magnitude of its motion do not change. Furthermore, when an object is not in motion, the direction and magnitude of its motion do not change unless an external force is applied to it. In other words, it means that the object remains stationary. This law explains many phenomena we experience in our daily lives. For example, when a car brakes suddenly, our bodies are thrown forward due to the law of inertia. Isaac Newton believed that force was the only thing that caused objects to move. An example of this is when you shake the dust off a blanket, the blanket moves, but the dust remains on the floor. Another example is when you scoop up dirt and throw it, even if your hand stops in midair, the dirt continues to fly. As you can see, the law of inertia is a basic principle that is easy to understand through everyday experience.
The second of the three laws is the law of acceleration. Better known as the equation F=ma, this law states that an external force applied to an object causes a change in the object’s state of motion. Acceleration is proportional to force and inversely proportional to mass. Here, m and a, i.e., mass and acceleration, are measurable physical quantities, but F, i.e., force, cannot be measured directly. Newtonian mechanics presents a method for calculating these forces. For example, when pushing a car, pushing it lightly will cause it to move slowly, but applying more force will cause it to move faster. This law can be used under the assumption that the mass of an object does not change. If the mass of an object changes, a different equation must be used to calculate the force.
For example, if a rocket loses mass as it consumes fuel, a more complex law of dynamics must be applied instead of the simple equation F=ma. The last law is the law of action and reaction. When object A exerts a force on object B, object B exerts a force on object A that is equal in magnitude and opposite in direction. Let’s look at an easy example.
Try hitting a wall with your hand. Even though you hit the wall, it hurts as if the wall hit your hand. It is important to understand that this law does not mean that B exerted a force on A, and as a result, B exerted a force on A. Rather, these two forces exist simultaneously from the beginning. This law plays an essential role in explaining many phenomena that we experience.
For example, when a rocket is launched into space, fuel is burned in the rocket engine and the resulting gas is ejected downward with great force. The force generated at this moment pushes the rocket upward, which is explained by the law of action and reaction. The force of the rocket ejecting fuel downward (action) acts as a force pushing the rocket upward (reaction). This principle cannot be explained without Newton’s law of action and reaction.
As such, Newton’s three laws are essential for understanding and explaining various phenomena that occur not only in physics but also in our daily lives. His theories are not mere theoretical concepts, but explain how the world we observe actually works. For example, when a moving car brakes suddenly, the passengers are thrown forward due to the laws of inertia and acceleration. Furthermore, the reason why ships can float on water is also closely related to these three laws. Ships float because they push water away, and the water pushes the ship up. This is an example of the law of action and reaction.
In addition, Newton’s laws are used as important principles in various fields of engineering, such as mechanical engineering, aeronautical engineering, and architectural engineering. Based on Newton’s laws, we can design and build modern complex machines and structures. For example, when designing a high-rise building, calculations of wind force and building weight are all based on Newton’s laws. As such, Newton’s laws play an indispensable role in science and engineering.
Although Newton’s physics was presented in the 17th century, its influence is still strong today. His theories were supplemented in the 20th century by Albert Einstein’s theory of relativity and the development of quantum mechanics, but Newton’s laws are still valid for explaining most of the phenomena we encounter in our daily lives. In this way, Newton’s physics remains the basic framework of modern science, unchanged by the passage of time.
Another important significance of Newton’s physics lies in the fact that he laid the foundation for scientific methodology. By presenting a methodology that combined experimentation and mathematical analysis to explain natural phenomena, Newton laid the foundation for science to develop in an objective and reproducible manner. As a result, science gradually established itself as an independent field of study, distinct from philosophy and theology.
In modern times, new theories that go beyond Newton’s laws have been proposed, but Newton’s achievements remain the foundation of science. For example, quantum mechanics and the theory of relativity deal with extreme situations where Newton’s laws do not apply, but Newton’s laws still apply on an everyday scale. This shows how universal Newton’s laws are and how deeply rooted his scientific achievements are.
Ultimately, Newton’s three laws are essential tools for understanding the world we live in. These laws are not just confined to science textbooks, but play an important role in understanding the reality we experience every day. Newton’s physics is still alive, and his laws remain an indispensable key to understanding the world.
