Laws of motion

 Sir Issac Newton formulated the three laws of motion in physics. 

Newton's first law- Every body continues in its state of rest or of uniform motion unless an unbalanced external force acts on it. 

Newton's second law- The rate of change of momentum of a body is directly proportional to unbalanced external force acting on it. 

F=ma, m is the mass and a is the acceleration 

Newton's third law- For every action  there is an equal and opposite reaction. 

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