Physics and Newton's Third Law of Motion

Newton's 3rd law states that for every action there is an opposite and equal reaction. Put another way when you push on an object it pushes you back.

Newton's 3rd law starts with conservation of momentum Conservation of momentum states  that the total change in a system’s motion to be zero. As a result moving a mass requires moving another mass in the opposite direction.

Rockets are the best example and the flame that is seen coming from the bottom of the rocket is propellant mass that is being ejected from the engines. This mass provides the action whose reaction pushes the rocket forward. Jets work on same basic principle but the main differ deference between a jet and a rocket is that jets take in air as part of their propellant mass making them more efficient than rockets since they are nor required to carry all that mass onboard.

The basic concept of Newton's 3rd law is that two masses push on each other with equal force. Equal mass will move away at the same speed. When one mass is smaller the other and if the force is kept the same, the smaller mass moves away faster and the heavier mass moves at the same speed as before. If one keeps the masses the same as in the last example but this time the force is larger then they both fly apart faster. The smaller mass still moves much faster than the larger mass.

One thing that is a little counter interactive is the fact that when a car that is being driven down the road, the Earth is actually being pushed in the opposite direction. To be fair this affect is extremely small but it is sill not zero and the traffic that is going opposite direction averages out to zero net force. It gets even stranger since even when you are just walking around you are actually pushing the Earth in the opposite direction. Once again it is still an extremely small, in fact much smaller than in a car; but still not zero. Furthermore all the people and animals in the world the affect will still average out to be zero. Like wise when a planet moves around its star the planet pulls back on the star causing it to wobble slightly. This is a main way that extra Solar planets are detected.  

Newton's 3rd law of Motion boils down to the fact that when one object pushes on another object, the second object pushes back. It is an important part of every change in motion in the universe because with out it no changes in motion would ever occur in the universe.

Newton's Second Law of Motion and Physics

The principle that states that a mass acted on by a force undergoes acceleration in the direction of the force, with a magnitude inversely proportional to the mass and proportional to the force is called  Newton's 2nd Law of Motion.

According to Newton's 2nd Law a force that is applied to a mass produces a steady increase in speed. Also decreasing the mass and increasing the force produces a faster increase in speed, while increasing the mass and decreasing the force produces a slower increase in speed.

Every change in motion in the Universe is based on Newton's 2nd Law including both changes in speed and direction. It is indeed fundamental to understanding of motion since without it changes in motion can not be properly understood.

Newton's first Law of Motion an important law of Physics

Newton's 1st Law of Motion states that a body will remain in motion or remain at rest unless it is acted on by an out side force. This law is also known as the law of inertia because inertia is the resistance to changes in motion. Newton's first Law shows that an object continues to move without changes in its motion until a force is imparted on it.

Every movement we make uses of Newton's 1st Law. Without the fist law of motion controlling motion is probably not even be possible. All possible methods of controlling motion depend on the first law. The 1st law of motion shows that motion remains the same without an outside force. We use it in every move we make.