Transcript laws of motion - science8wamogo

HAPPY WEDNESDAY!
•Please get your folders.
•If you finished your graph and
conclusions for Part 2, have them out.
•Copy down tonight’s homework.
Today, we will:
Talk about Newton’s 1st Law of Motion
Warm-up
Try to do the demonstrated action.
Write about what you think is going on.
Use the words “force” and “motion” in
your answer.
Sir Isaac Newton (1643-1727)
was an English scientist and
mathematician. He was
famous for his discovery of the
law of gravity, and he also
discovered the three laws of
motion. And calculus…
Newton’s First Law
An object at rest stays at rest
and an object in motion stays in
motion at constant velocity
unless acted upon by an
unbalanced force.
WHAT DOES THIS MEAN???
Basically, an object will keep doing
what it is already doing unless acted
on by an unbalanced force.
If the object was sitting still, it will
remain stationary. If it was moving,
it will keep moving at the same speed
in the same direction.
It takes force to change the motion of
an object.
How does Newton’s First Law
apply to this movie?
Play Movie
Newton’s 1st Law is also called
THE LAW OF INERTIA
Inertia is a physical property of
matter. It describes an object’s
resistance to changes in its motion.
Newton’s 1st Law states that all
objects have inertia.
The more mass an object has, the
more inertia it has (and the harder
it is to change its motion).
SOME REAL LIFE EXAMPLES:
A powerful locomotive
begins to pull a long line of
boxcars that were sitting at
rest. Since the boxcars
are so massive, they have
a great deal of inertia and
it takes a large force to
change their motion. Once
they are moving, it takes a
large force to stop them.
On your way to school, a bug
flies into your windshield.
Since the bug is so small, it
has very little inertia and
exerts a very small force on
your car (so small that you
don’t even feel it).
Example of an object having large inertia:
USS Nimitz:
Length: 332m (1092 feet)
Beam (width): 40.8m (134 feet)
Mass: 86,183,000 kg (190 million pounds)
Speed: 15 meters/second (34 mph)
So if the carrier is moving at 34 mph and
shuts its engines down, how far will it
drift?
A hundred feet? A thousand feet? A mile?
In turns out that the stopping
distance (in a smooth sea) would
be about 32 km (20 miles), if no
active measures are taken to stop
the forward motion of the carrier
(such as reversing the engines).
I don’t have a video of the USS Nimitz,
but check this out!
ARE YOU READY FOR SOME
MAGIC???
Attempt by the Mythbusters,
in slow motion…
Yeah, that was fake…
Could you tell how???
Before you leave…
 What is inertia?
 The glass that you brought up to
your bedroom is sitting on the floor next
to your bed. What does Newton’s 1st
Law say about that glass?
 You hit a fly ball toward left field.
What does Newton’s 1st Law say about
that ball?
 Huh??? Was Newton crazy???