Sir Isaac Newton’s Three Laws of Motion

"Nature and Nature's Laws lay hid in night; God said, 'Let Newton be!' -- And all was light." ( Pope .) Sir Isaac Newton 1642 - 1727

Three Laws of Motion 1. Law of Inertia 2. Law of Acceleration 3. Law of Interaction

I. The 1 st Law of Motion

Law of Inertia An object at rest will remain at rest, and an object in motion will remain in motion with constant velocity unless acted upon by an external force. In other words….

a) Balanced and Unbalanced Forces

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The seat belt provides the unbalanced force which brings you from a state of motion to a state of rest. Perhaps you could speculate what would occur when no seat belt is used. Click here for better understanding on Newton’s First Law.

If the truck were to abruptly stop and the straps were no longer functioning, then the ladder in motion would continue in motion.

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II. The 2 nd Law of Motion

The acceleration of an object as produced by a net force 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 object. Law of Acceleration F net = m . a

It accelerates in the direction that you push it. If you push twice as hard, it accelerates twice as much. If it gets twice the mass, it accelerates half as much. F net = m . a Click here for better understanding on Newton’s Second Law.

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III. The 3rd Law of Motion

Law of Interaction In every action, there is always an equal and opposite reaction Click here for better understanding on Newton’s Third Law.

The elephant's feet push backward on the ground; the ground pushes forward on its feet. The right end of the right rope pulls leftward on the elephant's body; its body pulls rightward on the right end of the right rope. The left end of the right rope pulls rightward on the man; the man pulls leftward on the left end of the right rope. The right end of the left rope pulls leftward on the man; the man pulls rightward on the right end of the left rope. The tractor pulls leftward on the right end of the left rope; the left end of the left rope pulls rightward on the tractor. etc., etc.

Click for more understanding. up, up and AWAY! Let's study how a rocket works to understand Newton's Third Law.

Summary

Thank You Very Much!!! Prepared By Kathleen Joy N. Buot