Laws Of Motion: Everyday Applications And Real-World Examples

Newton's laws of motion are three physical laws that establish the science of kinematics. These laws describe the relationship between the motion of an object and the force acting on it. They are essential because they are the foundation of classical mechanics, one of the main branches of physics. Newton's laws of motion are at play in nearly every physical action of our daily lives. For example, they control how cars work, how water flows, and how buildings don't fall down. They also explain why a rolling ball stops when it hits a wall, why you fall in the forward direction when a car stops suddenly, and why small balls roll faster than large balls.

Why we don't fall out of bed

Newton's laws of motion explain the relationship between a physical object and the forces acting upon it. These laws tell us how things move or stay still, and they are the basis of modern physics. Newton's laws control how everything around us moves, from cars and water to buildings and people.

Newton's First Law of Motion, also known as the Law of Inertia, states that an object at rest remains at rest, and an object in motion remains in motion at a constant speed and in a straight line unless acted on by an unbalanced force. In simpler terms, this means that a static body will remain static unless it is affected by external forces, and a moving body will not change its velocity as long as no external force affects it.

So, why don't we fall out of bed? Well, when we sleep, our bodies are still aware of our body position and movements, and this awareness develops over time. Most of us have enough awareness to ensure that we do not fall out of bed. This awareness can be attributed to Newton's First Law of Motion, as our bodies are the objects in motion, and the bed is the external force keeping us in place.

Additionally, Newton's Second Law of Motion states that the acceleration of an object depends on the mass of the object and the amount of force applied. When we are in bed, our body mass and the force of gravity pulling us down are counteracted by the force of the bed pushing up against us, keeping us in a stationary position.

Furthermore, Newton's Third Law of Motion, the Law of Action and Reaction, states that for every action, there is an equal and opposite reaction. When we are in bed, the force of our bodies pushing down on the bed is met with an equal and opposite force from the bed, pushing us back up.

In summary, we don't fall out of bed because our bodies are either in a state of rest or are being acted upon by the external force of the bed, as described by Newton's First Law of Motion. Additionally, the forces acting on our bodies, such as gravity, are counteracted by the equal and opposite forces exerted by the bed, as outlined in Newton's Second and Third Laws of Motion.

How cars work

Newton's laws of motion are three physical laws that establish the science of kinematics and describe the relationship between the motion of an object and the forces acting on it. These laws are essential as they are the foundation of classical mechanics, one of the main branches of physics. Newton's laws of motion are applied to everyday life, including how cars work. Here is how cars work, explained through the lens of Newton's laws of motion:

Newton's First Law of Motion

The first law of motion, also known as the Law of Inertia, states that an object at rest will stay at rest, and an object in motion will stay in motion unless acted on by an external force. In the context of a car, this means that once the car is put into motion, it will continue moving forward unless another force acts against it. This law explains why a car in neutral will eventually come to a stop due to the presence of opposing forces, most commonly friction. Friction acts on a moving car through the tires on the ground and the air flowing over the car, gradually slowing it down.

Newton's Second Law of Motion

The second law of motion, also known as the Law of Acceleration, states that when an object in motion encounters a force, its speed and direction will change in the direction of the force applied. The amount of change in motion is proportional to the force applied and inversely proportional to the object's mass. In the context of a car, this means that a larger force will cause quicker changes in motion, and a heavier car will react more slowly to forces. For example, a powerful car with a lightweight body can accelerate quickly and change directions swiftly.

Newton's Third Law of Motion

The third law of motion, also known as the Law of Actions and Reactions, states that for every action, there is an equal and opposite reaction. In the context of a car, this means that when the engine starts and makes the wheels spin, the wheels push against the road, and the road applies an opposing force that enables the car to move forward. Additionally, when brakes are applied, they cause the tires to push forward against the ground, and the ground pushes back, slowing the car down.

In summary, Newton's laws of motion play a crucial role in understanding how cars work. By applying these laws, we can explain how cars move forward, accelerate, decelerate, and change directions. These laws also highlight the importance of factors such as friction, mass, and external forces in the functioning of automobiles.

How buildings don't fall down

Newton's laws of motion govern several aspects of our daily lives, from getting out of bed to travelling by car or plane. They also explain how buildings don't fall down.

Buildings are not designed to fall straight down. When a building collapses, it does so because of the physical laws of gravity. Buildings are hollow, so when they get destroyed, each floor collapses onto the floor underneath, making the whole building fall vertically. This is known as a pancake collapse.

Buildings tend to collapse in a straight line, but they may lean towards certain sides at some points during the collapse. Ultimately, gravity takes over, and the building falls straight down.

There are several factors that can cause a building to collapse, including fires, earthquakes, and controlled demolitions. When a building collapses, it loses its primary support from the place where it was destroyed. For example, if the ground floor of a building collapses, it loses its main support point on the ground, causing the next floor to collapse, and so on.

In the case of controlled demolitions, experts may use explosives to create an implosion, causing the building to fall on its own base without leaning towards adjacent buildings. They can also make the building fall on a particular side by removing the supporting point on that side.

While buildings may not always fall in a perfectly straight line, the overall collapse tends to follow a straight path due to the nature of the structure and the force of gravity.

How planes fly

Newton's laws of motion are three physical laws that establish the science of kinematics and describe the relationship between the motion of an object and the force acting on it. These laws are important because they are the foundation of classical mechanics, one of the main branches of physics. Newton's laws of motion can be applied to everyday life in numerous ways, such as understanding how cars work, how water flows, and how buildings remain standing.

Now, let's delve into the topic of how planes fly, applying the principles of Newton's laws of motion.

The ability to fly across the globe in a matter of hours is a remarkable feat, with over 100,000 planes taking to the skies daily in the US alone. Understanding how planes achieve flight involves grasping the interplay between their engines and wings. While engines play a crucial role in propelling planes forward at high speeds, it is the wings that generate lift and keep the aircraft aloft.

The Role of Wings:

Wings are the key to achieving flight. They are designed to alter the direction and pressure of the air flowing over them, which results in lift. Most airplane wings have a curved upper surface and a flatter lower surface, forming a shape known as an airfoil or aerofoil. This curved shape deflects air and creates an area of low pressure above the wing, while increasing pressure beneath it. As a result, the wing experiences an upward force, known as lift, which counteracts the plane's weight and holds it in the sky.

The amount of lift generated depends on the angle of attack, which is the angle between the wing and the oncoming air. By adjusting this angle, pilots can control the amount of lift produced. However, if the angle becomes too steep, the airflow around the wing becomes turbulent, leading to a loss of lift and a condition known as a stall.

The Engines' Contribution:

While wings are essential for lift, engines play a crucial role in moving the plane forward at high speeds. Jet engines, in particular, generate a significant amount of thrust by burning fuel and air, producing hot exhaust gases that are expelled backward. This action propels the plane forward, creating a current of air over the wings. The faster the plane moves, the more air flows over the wings, increasing the lift generated.

Newton's Laws in Action:

Newton's third law of motion, often referred to as the law of action and reaction, explains how the engines and wings work together to keep a plane airborne. The force of the hot exhaust gases shooting backward from the jet engine pushes the plane forward, in accordance with Newton's third law. This forward motion creates a current of air over the wings, which then force the air downward. According to Newton's third law, the plane experiences an equal and opposite reaction, resulting in an upward force that lifts the plane into the air.

In summary, planes fly due to a combination of wing design, engine power, and the principles of Newton's laws of motion. By shaping the wings to create areas of high and low pressure, engineers harness the power of airflow to generate lift. Additionally, the forward thrust provided by the engines increases the speed of airflow over the wings, further enhancing lift.

How we play sports

Playing sports involves a lot of motion, and Newton's laws of motion can explain how athletes move and how sports equipment works.

Newton's first law of motion, also known as the law of inertia, states that an object at rest will remain at rest, and an object in motion will continue moving with a constant velocity unless acted upon by an external force. In sports, this can be seen when a ball is thrown. If no external forces were acting on the ball, it would continue travelling in the same direction forever. However, gravity acts on the ball, pulling it down towards the earth. Athletes must judge the force of gravity to find the right line of trajectory so that the ball goes where they want it to. For example, a basketball player shooting for the hoop must account for the force of gravity to ensure the ball arcs into the basket.

Newton's second law introduces the relationship between force and acceleration. It states that the force applied to an object is directly proportional to its mass and acceleration. This can be seen in sports when athletes throw or hit balls. The greater the mass of the ball, the more force is needed to accelerate it. For example, a baseball pitcher throwing a pitch must exert enough force on the ball to accelerate it to the desired speed and trajectory. Similarly, in tennis, the acceleration of the player's racket allows a maximum amount of force to be applied to the ball.

Newton's third law states that for every action, there is an equal and opposite reaction. This can be seen in sports such as golf, where the golfer swings their club to hit a stationary ball. During impact, the club applies force to the ball, and the ball pushes back on the club with an equal and opposite force. This force is minimal due to the difference in mass between the ball and the club, but it still causes the club to slow down slightly.

In addition to these three laws, Newton's law of universal gravitation also plays a role in sports. This law states that any two objects in the universe attract each other with a force that is directly proportional to their masses and inversely proportional to the square of the distance between them. In sports, this law can explain the trajectory of a basketball as it arcs towards the hoop.

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