Transcript Newton`s 1st Law

Newton’s
st
1
Law
Newton’s 1st Law
Newton’s First Law = an object at rest stays at
rest and an object in motion stays in motion
with the same speed and same direction (aka
velocity) unless acted upon by an outside force
Since inertia is the tendency of an object to
resist changes in velocity, Newton’s 1st Law is
also known as the Law of Inertia
With Balanced Forces (in Equilibrium):
• When forces are balanced, velocity remains the
same and acceleration equals 0 m/s2
With Unbalanced Forces:
• If forces are unbalanced then an outside force
is acting upon the object; acceleration does not
equal zero and velocity is changing
How does mass affect inertia?
All objects resist change but the more mass an
object has the greater the tendency to resist
changes
Newton’s 1st Law
Can anyone think of some everyday
examples of the Law of Inertia?
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Drink in a cup in the car (think of what
happens to the liquid when you suddenly
stop or go)
Slam on your brakes in your car but you
slide forward (the equal but opposite force
that stops your inertia is the seatbelt)
Getting ketchup out of the bottle