# First low of newton

## Newton's Laws of Motion More on Newton's first law of motion - Physics - Khan Academy

2017

A little bit stuffy, bad hair, but quite an intelligent guy. He worked on developing calculus and physics at the same time. During his work, he came up with the three basic ideas that are applied to the physics of most motion NOT modern physics. The ideas have been tested and verified so many times over the years, that scientists now call them Newton's Three Laws of Motion. First Law The first law says that an object at rest tends to stay at rest, and an object in motion tends to stay in motion, with the same direction and speed. Motion or lack of motion cannot change without an unbalanced force acting. If nothing is happening to you, and nothing does happen, you will never go anywhere.

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. It may be seen as a statement about inertia, that objects will remain in their state of motion unless a force acts to change the motion. Any change in motion involves an acceleration, and then Newton's Second Law applies. The First Law could be viewed as just a special case of the Second Law for which the net external force is zero, but that carries some presumptions about the frame of reference in which the motion is being viewed. The statements of both the Second Law and the First Law here are presuming that the measurements are being made in a reference frame which is not itself accelerating. Such a frame is often referred to as an "inertial frame". The statement of these laws must be generalized if you are dealing with a rotating reference frame or any frame which is accelerating.

## Newton's laws of motion

Newton's Laws: Crash Course Physics #5

## Newton's First Law

Newton's laws of motion are three physical laws that, together, laid the foundation for classical mechanics. They describe the relationship between a body and the forces acting upon it, and its motion in response to those forces. More precisely, the first law defines the force qualitatively, the second law offers a quantitative measure of the force, and the third asserts that a single isolated force doesn't exist. These three laws have been expressed in several ways, over nearly three centuries, [a] and can be summarised as follows:. Some also describe a fourth law which states that forces add up like vectors, that is, that forces obey the principle of superposition.

Sir Isaac Newton first presented his three laws of motion in the "Principia Mathematica Philosophiae Naturalis" in His first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force. This is normally taken as the definition of inertia. The key point here is that if there is no net force resulting from unbalanced forces acting on an object if all the external forces cancel each other out , then the object will maintain a constant velocity. If that velocity is zero, then the object remains at rest. And if an additional external force is applied, the velocity will change because of the force. The amount of the change in velocity is determined by Newton's second law of motion.

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## More on Newton's first law of motion

Sir Isaac Newton's three laws of motion describe the motion of massive bodies and how they interact. While Newton's laws may seem obvious to us today, more than three centuries ago they were considered revolutionary. Newton was one of the most influential scientists of all time. His ideas became the basis for modern physics. He built upon ideas put forth from the works of previous scientists including Galileo and Aristotle and was able to prove some ideas that had only been theories in the past. He studied optics, astronomy and math — he invented calculus.

The motion of an aircraft through the air can be explained and described by physical principals discovered over years ago by Sir Isaac Newton. Newton worked in many areas of mathematics and physics. He developed the theories of gravitation in , when he was only 23 years old. Some twenty years later, in , he presented his three laws of motion in the "Principia Mathematica Philosophiae Naturalis. Newton's first law states that every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force. This is normally taken as the definition of inertia.

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1. Laurent D. says:
2. Baptiste B. says: