Transcript powerpoint - Net Start Class

What is Newton’s First Law?
My first law states
that an object at rest
will stay at rest, and
an object in motion
will stay in motion
until acted on by an
unbalanced force. .
Also known as the Law of Inertia.
Inertia is the resistance of an object
to change its state of motion.
The skateboarder is moving at a
constant speed and direction. She
will eventually stop because of the
force of friction acting on the wheels.
FRICTION
When the Cowboy’s pass
is intercepted by the
Texans, the path of the
ball is stopped. An
unbalanced force has
acted upon the ball and
changed its direction.
When the baseball is hit by the batter, it flies in
the air. INERTIA says that it will stay moving in
the same path at the same speed. GRAVITY
forces the ball to change its path.
What is Newton’s
Second Law?
My second law states
that the acceleration
of an object depends
on the mass of the
object and the amount
of force applied to
the object.
Acceleration
is a of
Velocity
is a measure
speed andindirection.
CHANGE
velocity.
NEGATIVE
POSITIVE
ACCELRATION
ACCELRATION
isis a
andecrease
increaseinin
speed.
speed.
Acceleration also changes
when a direction changes.
Mass is the amount of
matter in an object!
Weight is the amount
of matter in an object
along with the pull of
gravity
Force is….
PUSH
or
PULL
How does mass affect acceleration?
When you smack a tennis ball as hard as you
can with a tennis racket, the ball flies far
and fast.
The more mass
equals less
acceleration
Try using that same racket with the same
force but with a baseball instead. What’s
going to happen?
The ball doesn’t go as far or as fast and
you’re lucky if your racket doesn’t end up
looking like this guy’s. Ready
Why? For
more about
As the mass of the ball
goes
up, your force
the
second
better go up, too, or the law?
ball is not going to
accelerate as fast.
How does force affect acceleration?
Let’s say crazy old Mike Tyson gives you a
pat on the head because he’s proud of you
for getting an A on your science test.
The more force
equals more
acceleration
Now let’s say crazy old Mike Tyson pounds on
your face as hard as he can because…well,
because he’s crazy like that.
I’m so
proud
of
That’s
the effect
you.
of different
masses. How
about to
thetake
effect
Want
a wild guess which one
of different
is going
to send you flying into the
next forces?
county? And we haven’t even
stopped to count your ears yet.
Newton’s Second Law
The larger the mass, the slower the motion.
The smaller the mass, the faster the motion.
The larger the force, the faster the motion.
The smaller the force, the slower the motion.
So let’s
Thesum
smaller the
up force,
that the slower the
Smaller equals quicker.
second
law. and vice versa.
motion
Force = Mass X Acceleration
F=ma
The acceleration of an
object depends on the
mass of the object and
the amount of force
applied to the object.
What is Newton’s Third Law?
Basically, forces come in pairs. Wherever there
Need proof? When you push off the wall while
is one force there is always another.
swimming, your feet push on the wall, and the wall
pushes on your feet.
My 3rd law states
that for every action,
there is an equal and
opposite reaction.
When rowers move the paddle it exerts a
force on the water. The water also exerts a
force on the paddle.
The two forces are equal and in opposite
directions.
The space shuttle’s engine is the initial force
pushing on the ground.
The
opposite
force is the
ground
pushing on
the space
shuttle.
So how do the
row boat,
swimmer, and
the space
shuttle move??
Remember my second
law?? It all comes down
to mass. The object with
larger mass exerts a
stronger force on the
smaller object, causing it
to move!