01.03

Newton’s Laws of
Motion
There' are three types of motion in
Newton’s law:
Newton's first law: A body not acted upon by an external resultant force moves with constant velocity or is at rest. Newton's second law: F=ma
Newton's third law: Every action has an equal and opposite reaction.

First Law
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Newton’s First Law - An object at rest (not moving) will stay at rest unless a force acts on it. An object in motion will stay in motion (in a straight line and at a constant speed) unless a force acts on it.

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Soccer example: When the ball is still, there is no way than object will move unless an opposite force does.

Second Law
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The acceleration of an object depends directly upon the force acting on the object.
As the force acting on an object increases, the acceleration increases. If the force acting on the object decreases, acceleration decreases. This is something that you have probably experienced for yourself. If you push your little sister on the swing set with a good push, she will accelerate a lot faster than if you pushed her lightly with just one arm. •

Soccer example: Once the ball has been kicked by the player, the acceleration of ball is directly proportional to the net force and inversely proportional to the mass. When you kick the ball, the more force you use to move the ball the greater the acceleration in the ball there is.

Third Law
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For every action (force applied) there is an equal and opposite reaction
(resulting force) that will occur.