Transcript Gravity Motion - Hicksville Public Schools / Homepage

AIM: Describe the factors that effect the strength of gravity
and how inertia differs from gravity?
OBJ: Given notes, images and activity sheet SWBAT
describe the factors that effect the strength of gravity and
how inertia differs from gravity with 70% accuracy
DN: HW check- Earth in Space Activity Sheet
ACT: Introduction to Gravity and Inertia (notes)
Complete Earth’s Motions Activity Sheet
HW: Text, read 16-19, Complete Gravity & Motion Activity
Sheet; Work on Astronomy Activity Sheet; Astronomy
Exam, Dec 19. Weather & Climate (Red) Textbooks due
Dec 18,19.
GRAVITY
Force: a push or pull
Gravity: attractive force between objects
containing mass [In reality, gravity is the warping
of spacetime by objects in the universe].
Gravitational Force Unit: newton, N
Two factors affect gravity: 1) mass of the
object’s, 2) distance between objects.
F(g) = M1 x M2_
d2
Gravity
Gravity
Mass
Mass: amount of matter (atoms) in an object
Weight: force of gravity on an object’s
mass.
Weight = mass x gravity
Note: object’s mass doesn’t change but
object’s weight changes due to change in
gravity because planets/moon vary in size.
Distance
gravity
Gravity decreases, as distance increases
Gravity increases, as distance decreases
Inverse relationship
distance
Inertia
Inertia: tendency of an object to resist a
change in motion.
Newton’s first law of motion:
Objects at rest, remain at rest
Objects in motion, remain in motion (at constant
speed & direction) . . . unless acted on by a
force.
Inertia
Orbital Motion
Orbit is due to two (2) factors:
1] gravity
2] inertia
inertia