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Understanding Laws of Motion

Newton laws are one of the most important topics in physics. Issac Newton has derived laws depending on the universal experience of motion. When an object shifts from one place to another, there will be changes in motion related to mass & force. Read more!

A genius found the foundational concept of physics just by sitting under an apple tree. Newton is a revolutionary scientist who discovered the concept of gravitational force in the year 1686. He gave multiple important inventions and theories in both physics and maths. Newton’s laws of motion are such important concepts that explain the experience of motion in universal objects.

In this article, we will get to learn more about the different laws of motion, inertia, acceleration, force, mass, etc. It will help in understanding the law of motion to a greater extent!

Explain Force and Laws of Motion

Force is the energy exerted on an object to change its location from one place to another. In most cases, this effect will take place between two objects or surfaces. 

Formula

Force is given as the product of the mass and the amount of acceleration force given to an object. 

Force, F = M x a

where, F denotes force

M denotes mass

a denotes acceleration 

The unit of force is given in Newton (N) which is derived from the name of the great scientist Sir Issac Newton.

Types of forces

  • Balanced force 
  • Unbalanced force 

Newton laws form the basics for every universal object that goes under any changes resulting in the alteration of its existing location. 

There are three major laws of motion.

  • First law of motion
  • Second law of motion
  • Third law of motion

Let us discuss each of these laws in detail.

Before that, we have to know about the definition of some important terms.

Inertia

A resistive force that makes a physical object incapable of altering its speed and motion (denoted as velocity) is known as inertia. It leads to restricting acceleration in the object and makes it remain idle. 

Inertia is directly proportional to the mass of a physical object. 

Momentum

Momentum is the product of mass and velocity of an object and is denoted as ‘p.’

Formula

Momentum, p = m x v

Unit of momentum – kg x m/s.

Newton’s First Law of Motion

When a physical body is idle or moving in a straight line at a constant speed, it will remain idle or continue moving in the straight line at the same speed until an external force is applied. Newton’s first law of motion can also be termed as the ‘law of inertia.’

Example

Consider that you are shaking a tree. In that situation, you can witness that the tree shakes but the fruits don’t. It is because the fruits remain in an idle position due to inertia. Ultimately, the fruits won’t experience any motion but instead, they will fall on the ground.

This shows the application stated in Newton’s first law of motion.  

Newton’s Second Law of Motion

When an object moves in the same direction similar to the force applied on it, then the force will be equal to the product of both acceleration and mass. 

In simpler words, a body remaining in an idle position will tend to move from its existing position when an external force is applied to it. Newton’s second law of motion can also be termed as the ‘law of force and acceleration.

Formula

F = m . a kg*m/s2

Example

Consider that two persons A and B are trying to push an idle car. 

Initially, only A pushes the car but can’t move it. It is because the force given by A is lesser than the force required to move the car. So, the car stays idle.

Then, B joins A and pushes the car. Now, the car starts to move forward due to the force given by both A and B. It results in the motion of the car for a certain distance. 

This shows the application stated in Newton’s second law of motion. 

Newton’s Third Law of Motion

When object A exerts a force on object B, then object B will exert the same amount of force on object A in the opposite direction. This phenomenon will always take place between two physical bodies. Newton’s third law of motion can also be termed as the ‘law of action and reaction.’

Example

Consider a situation where you throw a basketball towards the ground. Once it hits the ground, it bounces back against the floor. It is because the amount of force applied to the ball makes it revert back to you. 

This shows the application stated in Newton’s third law of motion. 

Conclusion

Ultimately, motion is described in terms of distance, time, velocity, acceleration, displacement, and speed. It is the measure of change in the position of a physical body from one place to another with time. Issac Newton was one of the greatest scientists who played a major part in deriving the different laws related to the different types of motion in an object. These laws of motion form the foundation of classical mechanics.

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Explain force and laws of motion.

Ans. Force is the energy exerted on an object to change its location from one place to another. New...Read full

When did Issac Newton discover laws of motion for the first time?

Ans.Sir Issac Newton introduced three foundational laws of motion in the year 1687 in his pu...Read full

What are the three laws of motion discovered by Newton?

Ans. First Law of Motion (alternatively called the law of ine...Read full

What is called inertia?

Ans. A resistive force that makes a physical object incapable of altering its speed and moti...Read full