# Newton’s laws and their applications

In physics Newton's three laws of motion are the basis of kinematics, the subject of this course. All three laws are detailed on this page. See also: Motion - Dynamics

## Newton's Laws of Motion

Newtons law describes the body's motion in terms of physics. It has been widely accepted by the science community for the past 10century, in total there were three laws that affect the laws of motion.

## Newton's First Law

His first law of motion is called the law of inertia, his law is; "Every body continues its state of rest or uniform motion until an external unbalanced force acts on it" ."" If a body is moving ,it will continue to move with the same speed in the same direction unless a force is applied on it" Newton put the above observation in the form of a law which is called the Newton's first law of motion.And the resultant force must be zero.

## Newtons Second Law

His second law is more notably named as the law of acceleration. His law is;

"The rate of change of momentum of an object is directly proportional to the resultant force acting on the body and is in the same direction."

This law means that the force of the object moving will be equal to the opposing force such as air resistance. Mathematically, Newton's second law is stated as:

${\displaystyle {\overrightarrow {\mathbf {F} }}={\frac {d{\overrightarrow {\mathbf {p} }}}{dt}}}$

where F is the total force, p is the momentum, and t is the time passed. In classical physics, where the object's mass is constant, this equation becomes a more familiar form:

${\displaystyle {\overrightarrow {\mathbf {F} }}={\frac {d{\overrightarrow {\mathbf {p} }}}{dt}}={\frac {dm{\overrightarrow {\mathbf {v} }}}{dt}}=m{\frac {d{\overrightarrow {\mathbf {v} }}}{dt}}=m{\overrightarrow {\mathbf {a} }}}$

where m is the object's mass and a is the acceleration of the object. Example

A skydiver jumps from a plane and accelerates until he reaches the highest velocity possible, when this happens his acceleration is equal to nothing, this happens when air resistance is equal to the downward force of the skydiver.

## Newton's Third Law of motion

Newton's third and final law is the law of Interaction in which he Doubted;

"All forces occur in pairs, and these two forces are equal in magnitude and opposite in direction." It can be said that "every action has an opposite and equivalent reaction"

Examples
1. When we push a wall, it creates an opposite amount of force, thus, either we move or does the wall move.

This in simple terms is that to every action force there is an equal, but still the same, reaction force. For example if one presses on a wall a equal and same force is pushed back at them.)