Sir Isaac Newton

Newton’s Laws of Motion Newton’s 1st Law of Motion -An object at rest, will remain at rest, unless acted upon by an unbalanced force. -An object in motion, will remain in motion, in a straight line, at constant speed, unless acted upon by an unbalanced force. INERTIA tendency of an object to resist motion

Newton’s 2nd Law of Motion - A force acting on an object will cause it to accelerate in the direction of the applied force -Objects with greater mass require more force to accelerate them -Objects with greater acceleration exert more force Force = mass x acceleration F = ma units: kg m/s/s Newton’s Laws of Motion

Newton’s Law of Motion Newton’s 3 rd Law of Motion -For every action, there is an equal and opposite reaction force. Force occurs in pairs ACTION = REACTION p = mv

Forces FORCE- push, or pull, of one object on another object - a force acting on an object causes the object to ACCELERATE FORCE = MASS X ACCELERATION F = m a Units: kg (m/s 2 ) = 1 NEWTON Instrument: Spring Scale

CONTACT FORCES -Forces resulting from contact between two objects Ex. Friction -the force that opposes motion between two contacting surfaces. air resistance- the force that opposes motion between an object and the air FIELD FORCES -Forces existing between two objects in the absence of contact Ex. Gravity-the force that every object in the universe exerts on every other object in the universe. Electromagnetic –force created by electricity/magnetism

BALANCED FORCE -equal/opposite forces -no motion is produced 500 N 500 N UNBALANCED FORCE–unequal/opposite forces -motion is produced 1000 N 500 N NET FORCE - F net, total sum of all forces acting on an object  F = sigma F = sum of forces in a particular direction

 F x = 500N -500N = 0N  F x = 1000N – 500N = 500N