Transcript Newton`s Laws of Motion

Warm-up
• What force:
– makes the flag outside
fly? wind
PUSH
PULL
– holds the paper to the
board? magnetism
– makes an apple fall down
PULL and not up? gravity
– makes a boat float? PUSH
buoyancy
– makes a balloon stick
to a wall after rubbing
PULL.
it? static electricity
• How are these forces similar and
different?
Some PUSH, while others PULL.
Newton’s Laws of Motion
Ch. 2.1, 2.2, 2.3
Sir Isaac Newton
• Born in England,
12-25-1642
• Died in 1727
• Formulated the law of
gravitation
• Invented calculus
• Stated laws of motion
Newton’s 1st Law of Motion
• States that objects at rest will remain at
rest and objects in motion will remain in
motion at the same velocity, unless
acted upon by a force.
• “Law of Inertia”
• The tendency of an object to remain in
motion or at rest is called inertia.
Example of Newton’s 1st Law
• A force is a push or
pull that changes
the motion of an
object.
• Listen to the car
example from your
teacher.
• Watch the inertia
example at the front
counter.
Example of Newton’s 1st Law
• What happens when you’re walking
with a cup filled high with a drink and
stop suddenly?
the drink spills out
• According to the 1st law, why does the
drink do this?
It has inertia and continues traveling
the speed you are walking at. When
you stop, it keeps going.
Newton’s Second Law of Motion
• States that the force needed to accelerate
an object is determined by the mass of
the object.
force = mass x acceleration
• The more mass an object has, the more
force is needed.
• The less mass an object has, the less
force is needed.
Examples of Newton’s Second Law
• If you used the same
amount of force to push
these 2 cars, which one
would move faster? Why?
Toy Car = less mass
• At which time would the
tan car move faster; if you
pushed it by yourself or
with 2 friends? Why?
2 Friends = more force
Newton’s 3rd Law of Motion
• States that when one object exerts force
on a second object, the second object
exerts an equal force in the opposite
direction.
• “Law of Action and Reaction”
Example of Newton’s 3rd Law
• Why is the frog jumping off a
lily pad an example of the 3rd law?
• What two directions is the frog moving as its
“jumping”?
Up and Forward
• Since it’s “the law of action and reaction”, what
two directions is the lily pad moving?
Down and Backward
Example of Newton’s 3rd Law
• What is happening to the swimmer’s body
as he pushes the water backwards?
Example of Newton’s 3rd Law
• It which direction is
the space shuttle
going?
upwards
• What is the force
moving it?
Rocket fuel fire
• In which direction is
the rocket “fire”
going?
downwards
Wrap-up
Write whether each frame is BEST demonstrating
Newton’s 1st, 2nd, or 3rd Law!