Chapter 12 Section 2
Gravity and Motion
Gravity
Is The FORCE that attracts all objects
towards each other.
Force - a push or a pull
For example when Sir Issac Newton
observed the apple fall to the ground, he
hypothesized that the apple was pulled
toward the Earth due the force of
gravity.
Universal Law of Gravitation
Every object in the universe attracts
every other object.
Who came up with the Universal Law of
Gravitation?
Sir Isaac Newton
The strength of the force of
gravity between two objects
depends on what 2 factors?
Mass of an object
Distance between 2 objects
Mass of an
object
Mass is the amount of matter in an object.
The MORE MASS an object has the MORE
gravitational force it exerts.
MASS stays the SAME no matter where you
are in the universe.
Weight of an
object
The force of gravity on an object is the
object's WEIGHT.
An object's weight CAN change depending on
its location.
Distance
The strength of gravity between two
objects is affected by the distance
between the two objects.
GRAVITY DECREASES
As
DISTANCE INCREASES
What 2 factors keep the Earth in
orbit around the Sun?
gravity
Inertia
Inertia
The tendency of an object to resist a
change in motion.
Orbital Motion
Earth revolves around the sun because
the Sun's gravity pulls on it while Earth's
inertia keeps it moving ahead.
This is an example of ORBITAL MOTION
Please Complete
Chapter 12 Section 2
Page 477 Questions
1a,b&c 2a,b&c