Newton’s law of Motion

Newton’s law of Motion

Newton’s law of motion is the three physical laws which provide relationships between the forces acting on a body and the motion of the body. We all know that Newton’s law consists of three laws, the law of Inertia, acceleration, and the law of action reaction.

The Newton’s first law is concerned with bodies at rest or those moving with constant velocity and assumes that no forces are acting to change their state. It is called inertia. Inertia is the property of a body to resists a change in its current state.
“Every body continues in its states of rest, or of motion in a straight line at constant speed, unless it is compelled to change that state by forces exerted upon it” p, 235(Santos, 2003) The Newton’s second law is called law of acceleration. “The acceleration produced by a net force on a body 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 body.” P.238 (Santos, 2003) The Newton’s third law deals with the action-reaction principle, like when you give a certain amount; you will also receive the same amount. What does Newton’s third law state? “Whenever one body exerts a force on a second body, the second body exerts an equal and opposite force on the first.” P.242 (Santos, 2003)

An example of the first law of motion is pulling the tablecloth out from under the dishes depends upon the inertia of the dishes, which keeps them from moving in the same direction as the tablecloth. This results from the force of friction between the tablecloth and the dishes. The dishes tend to stay at rest and fall straight down onto the table. Example of the second law of motion is like kicking a ball in a soccer game, because if you kick a soccer ball, it will speed up in the direction of the kick. If you kick it harder, more force is applied to the ball, making its speed faster in the same direction. In conclusion, the change in speed is directly related to the amount of force applied unto it. More force gives more acceleration and less force gives less acceleration. Example of the third law of motion is walking. As you walk across the floor, you exert force on the floor and the floor exerts an equal and opposite force on your foot pushing you forward. Another example would be rocket propulsion. As hot gasses are pushed out the bottom of the rocket, the gasses push upward on the rocket with the same force, accelerating the rocket so that it can escape the earth’s gravitational field.