How do Forces Affect Motion?
How do Forces Affect Motion
Force – a push or a pull on an object that can
cause it to change direction.
NOTHING moves, stops, or changes directions
with out FORCE.
Heavier objects need more force to get them to
move or change direction.
How do Forces Affect Motion
Gravity – a force that pulls two objects toward
each other because of their mass, such as you
toward the center of the earth.
Mass – a measurement of the amount of
material (matter) that makes up an object.
How do Forces Affect Motion
Weight – is a measurement of how hard the
earth’s gravity pulls on an objects mass.
The more mass and object has the more it
weighs.
More Mass = More Pull = More Weight
Something your parents don’t know!
Everything with mass has a gravitational pull
You have mass therefore you have gravity.
Not a lot, but still you have gravity!
Sir Isaac Newton
• A scientist in the 1600’s
• Discovered calculus
• Discovered white light
was a mixture of
colored lights
• Made discoveries in
motion, gravity, and
chemistry.
• Considered one of the
greatest scientists EVER.
Sir Isaac Newton
Discovered that objects will continue moving in a
straight line until a force causes it to slow down or
stop.
He also discovered that an object not moving, or at
rest, will stay at rest until a force, such as a push or
a pull, moves it.
This is called inertia, and is Newton’s 1st law of
motion (He has 3)
How do Forces Affect Motion
Inertia -The tendency of a moving
object to stay in motion or resting
object to stay at rest.
How do Forces Affect Motion
Now think about a soccer ball, according to
newton an object in motion will stay in motion
FOREVER, but if I kick a soccer ball will it stay in
motion FOREVER??
How do forces affect motion
No!
Because there is a force acting upon the ball and
that force is friction.
Friction - is a force that slows down the motion of
moving object.
There is friction between the ball and the ground.
How do Forces Affect Motion
So according to Newton if I kick the ball off the
ground, it wont have friction with the ground so,
it should stay in motion FOREVER.
No
It is still getting friction from the AIR.
And being pulled to the ground by Gravity!!!!