Classical mechanics: Difference between revisions
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==Newtonian Mechanics== | ==Newtonian Mechanics== | ||
===Newton's laws of motion=== | |||
Newton's laws of motion help to analyze the principles of [[dynamics]], the relationship of motion to the forces that cause it. These three laws were first published in 1687 in ''Philosophiae Naturalis Principia Mathematica''. | Newton's laws of motion help to analyze the principles of [[dynamics]], the relationship of motion to the forces that cause it. These three laws were first published in 1687 in ''Philosophiae Naturalis Principia Mathematica''. | ||
The first law states that: | The first law states that: | ||
'''A body acted on by no net force moves with constant velocity and zero acceleration.''' | '''A body acted on by no net force moves with constant velocity and zero acceleration.''' | ||
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The second law states that: | The second law states that: | ||
'''If a net force acts on a body, the body accelerates. The force equals the mass of the body multiplied by the acceleration.''' | '''If a net force acts on a body, the body accelerates. The force equals the mass of the body multiplied by the acceleration.''' | ||
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The third law states that: | The third law states that: | ||
'''If body ''A'' exerts a force on body ''B'', then body ''B'' exerts a force on body ''A''. This force will have an equal magnitude and opposite direction.''' | '''If body ''A'' exerts a force on body ''B'', then body ''B'' exerts a force on body ''A''. This force will have an equal magnitude and opposite direction.''' | ||
Revision as of 17:14, 11 August 2007
Classical Mechanics is the study of the effects of forces on bodies. It can be divided into two parts: Newtonian Mechanics, named after Sir Isaac Newton,and Relativity, developed by Albert Einstein.
Newtonian Mechanics
Newton's laws of motion
Newton's laws of motion help to analyze the principles of dynamics, the relationship of motion to the forces that cause it. These three laws were first published in 1687 in Philosophiae Naturalis Principia Mathematica.
The first law states that:
A body acted on by no net force moves with constant velocity and zero acceleration.
This means that a body in motion has a property called inertia, a tendency to keep moving unitl another force causes it to stop.
The second law states that:
If a net force acts on a body, the body accelerates. The force equals the mass of the body multiplied by the acceleration.
This relation of force and motion is a fundamental law of nature. If there is a constant net force acting on an object it's velocity will continue to increase at a constant rate of acceleration.
The third law states that:
If body A exerts a force on body B, then body B exerts a force on body A. This force will have an equal magnitude and opposite direction.
This is less formally stated as; every action has an equal and opposite reaction. It's important to remember these two forces act on different bodies.