Notes
SPI 0807.12.5
Gravity-Mass and Distance
Science
Tennessee SPI Objective:
Determine the relationship
among the mass of objects,
Instructions
the
and bar.
the amount of
1) distance
First clickbetween
on "View"these
from objects,
the top-menu
2) Then click on
"Slide Show" from the drop-down menu.
gravitational
attraction.
3) Then use the right-arrow button on your keyboard to
Check for Understanding
advance through this presentation.
Identify factors that influence the amount of
gravitational force between objects
Essential Question(s)
What is gravity? What is mass? How does mass and
distance affect gravitational pull?
Notes
SPI 0807.12.5
Gravity-Mass and Distance
Science
Gravity
 is a “mysterious” force found everywhere in the universe
that pulls particles of matter together
Key Concept: Gravity is a pulling force (not a pushing force)
Law of Universal Gravitation
F.Y.I -Isaac Newton is credited with defining this law
The law states that gravity is everywhere in our universe, and
that its attractive force changes based on mass and distance.
Reminder: Mass is the amount of matter in an object
Summary: Every particle of matter is attracted to every other
particle of matter.
Mass Affects Gravity
 Objects with more mass have stronger gravity
 Look below: (bowling ball and a baseball) both objects are
made of matter, so both objects have gravity.
 So both objects are being pulled towards each other.
 Yet the ball with more mass (bowling ball) has more gravity.
 Therefore its pull is stronger (view animation)
Diagram 01
(Imagine these objects are floating in space)
Mass Affects Gravity
 The example of a bowling ball and a baseball is similar to the
gravity effect with a planet and a moon
Diagram 01
Earth and the Moon
Notes
SPI 0807.12.5
Gravity-Mass and Distance
Science
Mass Affects Gravity
 Look below: (baseball and a golf ball) both objects are made
of matter, so both objects have gravity.
 So both objects are being pulled towards each other.
 Yet the ball with more mass (baseball) has more gravity.
 Therefore its pull is stronger (view animation)
 This is similar to the gravity effect with a moon and a asteroid
Diagram 02
(Imagine these objects are floating in space)
Notice the volume (size) of the Sun contrasted with Jupiter
 The Sun is bigger because it has more matter (mass)
 Because it has more mass, it likewise has more gravity
Note: The planets are not
actually this close to the Sun
Jupiter
Earth
Jupiter has more mass than Earth.
Therefore Jupiter has more gravity than Earth.
Earth
The Moon
The Earth has more mass than the Moon.
Therefore Earth has more gravity than the Moon.
Notes
SPI 0807.12.5
Gravity-Mass and Distance
Science
Distance Affects Gravity
 Affect of gravity increases when objects are closer together.
 Affect of gravity decreases when objects are farther apart.
In diagram 01 the two soccer balls are 5m apart (floating in space).
In diagram 02 the two soccer balls are 10m apart (floating in space.
Gravitation attraction is greatest when they are closer together.
Diagram 01
5 meters
Diagram 02
10 meters
SPI 0807.12.5
Gravity-Mass and Distance
Earth
The Sun
The Moon
Distance Affects Gravity

The Sun has more gravity than the Moon.

Yet the Moon is closer to Earth than the Sun.

So the Moon’s gravitation pull on Earth’s oceans
(tides) is greater than the Sun’s gravitation pull.
Gravity and the Theory of Relativity
F.Y.I. -Einstein theorized that mass warps (bends/curves)
space and this warping explains the force we call gravity.
Watch both of these Youtube videos:
Write down three things that catch your attention, and be
ready to share afterwards.
(1) Link: Curvature of Space-Time (34 sec)
(2) Link: How Gravity Really Works (1 min 45 sec)
Quick
Review
SPI 0807.12.5
Gravity-Mass and Distance
Science
1) What is the name of the law about gravity? The law of…
A) …Conservation of Mass or B) …Universal Gravitation
(2) All matter in the universe attracts other matter by?
A) A “pushing force” or B) A “pulling force”
(3) The strength of gravity depends on the ______ of the objects
A) Masses or B) Shape
4) Effect of gravity depends on the _____ between the objects.
A) Energy or B) Distance
5) What did Einstein say about mass and gravity?
A) That mass warps space or B) Mass and gravity are the same
Questions
SPI 0807.12.5
Gravity-Mass and Distance
Science
Here is an example of a question you might see on a quiz or test.
Questions
SPI 0807.12.5
Gravity-Mass and Distance
Science
Here is an example of a question you might see on a quiz or test.
Questions
SPI 0807.12.5
Gravity-Mass and Distance
Science
Here is an example of a question you might see on a quiz or test.
Questions
SPI 0807.12.5
Gravity-Mass and Distance
Science
Here is an example of a question you might see on a quiz or test.
Questions
SPI 0807.12.5
Gravity-Mass and Distance
Science
Here is an example of a question you might see on a quiz or test.