Download Newton`s Laws of Motion

Newton’s Laws of Motion
Law of Inertia
• Newton’s first law of motion – the law that states that an object will maintain its current state of motion unless it is acted
FN
upon by an unbalanced force
v
• Also called the law of inertia
FA
FF
• Inertia – a property of matter that describes an object’s tendency to resist a change in motion
• Mass – a measurement of the quantity of matter also related to inertia
Fg
• Law of inertia applies to both objects at rest and in motion
• Ex) The net force on the book is zero so it moves with a constant velocity
Force & Acceleration
• Newton’s second law of motion – the law that states that the acceleration of an object is directly related to the net force on
the object and inversely related to the mass of the object
net force = mass acceleration 𝐹!"# = 𝑚𝑎
• Units of newtons can be broken down
N = kg ∙
m
s!
Force Pairs
• Newton’s third law of motion – the law that states that for every action there is an equal and opposite reaction
• Force pair – a pair of equal and opposite forces applied between two objects
• Ex) Three force pairs between the mass, Earth, string, and ceiling
𝐹!"#$#%& !" !"#$%& = −𝐹!"#$%& !" !"#$#%&
𝐹!"#$%& !" !"## = −𝐹!"## !" !"#$%&
𝐹!"## !" !"#$% = −𝐹!"#$% !" !"##
Physics 3.2 – Newton’s Laws of Motion