Newton's Laws - Newton's Three Laws of Motion, Illustration,Examples and Explanation

 Have you ever tried throwing a ball while standing on roller skates? Have you ever imagined of stopping a running truck? Many such incidents in his macro world can be explained by means of Newton's three laws of motion or simply newton's laws. Want to know what are those force and laws of motion framed by Sir. Isaac Newton? Here you can learn the stated laws of Newton and also learn the some examples or illustration of Newton's first, second and third law.

Newton's Laws

Newton's Three Laws of Motion

Before going into the laws of motion first let us see some facts and information of Sir. Isaac Newton.

• Sir Isaac Newton was born on 25 December 1642 and he was well known as English physicist and mathematician.
• He wrote a book named Philosophiæ Naturalis Principia Mathematica known as Mathematical Principles of Natural Philosophy that was first published in 1687.This book paved way for classical mechanics.
• He formulated the laws of motion and universal gravitation.
• Based on the observation that a prism decomposes white light into  visible spectrum colours proposed theory of colour and Newton was the first one to built practical reflecting telescope.
• In 1704, Newton published Opticks in 1704 that revealed his corpuscular theory of light.
• IT has been said that the apple story is a myth and that Newton did not arrive at his theory of gravity in any single moment but through series of discoveries. But Newton himself said about the apple incident.

Newton's laws of motion

Now let us go through the Newton's Laws of Motion and learn the discoveries made by Sir. Isaac newton that helped the science to reveal many mysteries in this macro world.

Newton's First Law or Newton's First Law of Motion: 

Newton's First Law states," That an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force".

The Latin translation of this newton law is"Corpus omne perseverare in statu suo quiescendi vel movendi uniformiter in directum, nisi quatenus a viribus impressis cogitur statum illum mutare".

Explanation and Illustration of Newton's First law:
From this law of motion Sir. Newton explains us that any object at rest or in uniform motion will continue in its action unless it is disturbed such as action of moving or stopping by external force.
for example a book on the table will remain in rest till it is moved by a human and the rotation of earth around the sun will continue till the rotation is stopped by any external force such as asteroids. Also if any change occurs in the motion of an object it causes or involves acceleration, causing the external force to be zero. Hence this change shows us that newton's first law is a special case of newton's second law.
Now lets us see two pictures or images that explains us and helps us understand Newton's first more effectively.

fig 1: This image explaining Newton's first law was pictured by NASA from which we can learn how air planes fly on air on base on Newton's 1st law. The drag is directly proportional to the thrust which holds the aircraft with constant speed in air thus proving first law of Newton.

fig 2: This image too helps to understand the first law of newton clearly. Consider a stone attached to a string and rotate the stone in the path circle horizontally by holding the end of the string. This creates needed centripetal force for the stone to move in circle. Also the stone is moving in constant uniform motion and if the string is cut the stone will move in a straight line without external forces, this is an example proving Newton's first law.

Newton's Second Law or Newton's Second Law of Motion

The Latin translation of this newton law is,"Mutationem motus proportionalem esse vi motrici impressae, et fieri secundum lineam rectam qua vis illa imprimitur"

Which states or denotes that, " The acceleration of an object produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object"

Explanation and Illustration of Newton's Second law

This law of Newton can be explained as follows, "If a motion is caused by a force, the motion doubles as force is doubled, motion triples as force triples. Simply said velocity of an object changes as forces are induced. That is velocity of an object maintains unless force acts on it to cause acceleration.(Rate of change of velocity).It can also be said that heavier objects require more force to move than lighter objects for the same distance.

This law can be mathematically defined as

                                                                      F=ma

where m=mass and a=acceleration.

for example;

Consider a man trying to move a stone that weighs 1000kg and the stone moves at a rate of 0.5m/s, then according to the above formula F=ma, we can find the force by multiplying mass and acceleration i.e., 1000 x 0.5 = 500 newtons of force.

As this law aids in quantitative calculations of dynamics it is considered to be the most powerful of Newton's laws.

fig 1: The figure below explains the law in an effective manner. Small object has large acceleration for a given force and large object have small acceleration for the same given force.

Newton's Third Law or Newton's Third Law of Motion

Newton's third law states that," For every action there is an equal and opposite reaction" which is known by nearly every human on this earth. This law explains the fact that When one body exerts a force on a other body, the other body simultaneously exerts a equal amount of force in magnitude as well as in opposite direction on the first body.

When the original Latin language of this law is translated to English it reads like this, "To every action there is always opposed an equal reaction: or the mutual actions of two bodies upon each other are always equal, and directed to contrary parts".

Explanation and Illustration of Newton's Third law

1.For instance, Consider the motion of flying birds. A bird flies by use of its wings. The flapping wings of a bird pushes the air downwards and backwards. So as per newton's third law, the air must also push the bird upwards and forward direction, which keep the bird in motion of flying. The amount of the force by the bird on the air equals the amount of the force on the bird; the direction of the force on the air (downwards and backwards) is opposite to the direction of the force on the bird (upwards and forwards). Thus proving Newton's third law.

2.222   2.Also have you tried throwing a ball wearing skies in your legs? It will push u backward as you throw the ball forward. A cricket ball hitting a glass window shatters the glass in the direction opposite towards it impact. These are some examples of Newton's third law of motion.

3.The principle behind the lifting of rocket and its propagation is also Newton's third law.

Hope you have learnt a lot through this post.